Biocompatible Initiators for Lactide Polymerization

References

• Ragauskas , A. J. , Williams , C. K. , Davison , B. H. , Britovsek , G. , Cairney , J. , Eckert , C. A. , Fredrick , W. J. Jr. , Hallett , J. P. , Leak , D. J. , Liotta , C. L. , Mielenz , J. R. , Murphy , R. , Templer , R. and Tschaplinski , T. 2006 . The path forward for biofuels and biomaterials . Science , 311 : 484 – 489 .
   PubMed Web of Science ®Google Scholar
• Mecking , S. 2004 . Nature or petrochemistry? Biologically degradable materials . Angew. Chem. Int. Ed. , 43 : 1078 – 1085 .
   PubMed Web of Science ®Google Scholar
• http://www.natureworksllc.com/
   Google Scholar
• Södergård , A. and Stolt , M. 2002 . Properties of lactic acid based polymers and their correlation with composition . Prog. Poly. Sci. , 27 : 1123 – 1163 .
   Web of Science ®Google Scholar
• Carruthers , W. H. , Dorough , G. L. and van Natta , F. J. 1932 . Studies of polymerization and ring formation. X The reversible polymerization of six‐membered cyclic esters . J. Am. Chem. Soc. , : 761 – 772 .
   Google Scholar
• http://www.mitsui.com
   Google Scholar
• Amass , W. , Amass , A. and Tighe , B. 1998 . A review of biodegradable polymers: Uses, current developments in the synthesis and characterization of biodegradable polyesters, blends of biodegradable polymers and recent advances in biodegradation studies . Polymer Int. , 47 : 89 – 144 .
   Web of Science ®Google Scholar
• Lunt , J. 1998 . Large‐scale production, properties and commercial applications of polylactic acid polymers . Polym. Deg. Stab. , 59 : 142 – 152 .
   Google Scholar
• Drumright , R. E. , Gruber , P. R. and Henton , D. E. 2000 . Polylactic acid technology . Adv. Mater. , 23 : 1841 – 1846 .
   Web of Science ®Google Scholar
• Albertsson , A. C. and Varma , I. K. 2003 . Recent developments in ring opening polymerization of lactones for biomedical applications . Biomacromolecules , 4 : 1466 – 1486 .
   PubMed Web of Science ®Google Scholar
• Hartmann , M. H. 1998 . “High molecular weight polylactic acid polymers” . In Biopolymers from Renewable Resources Edited by: Kaplan , D. H. 367 – 411 . Berlin : Springer‐Verlag .
   Google Scholar
• Duda , A. and Penczek , S. 2000 . “Thermodynamics, kinetics and mechanisms of cyclic esters polymerization” . In Polymers from Renewable Resources: Biopolyesters and Biocatalysis , ACS Symposium Series Edited by: Scholz , C. and Gross , R. A. Vol. 764 , 160 – 199 . Washington, DC : Oxford University Press USA .
   Google Scholar
• A review of literature published until January 2007 is presented
   Google Scholar
• Inoue , S. 2000 . Immortal polymerization: The outset, development, and application . J. Polym. Sci., Polym. Chem. , 38 : 2861 – 2871 .
   Web of Science ®Google Scholar
• O'Keefe , B. J. , Hillmyer , M. A. and Tolman , W. B. 2001 . Polymerization of lactide and related cyclic esters by discrete metal complexes . Dalton Trans. , : 2215 – 2224 .
   Google Scholar
• Nakano , K. , Kosaka , N. , Hiyama , T. and Nozaki , K. 2003 . Metal‐catalyzed synthesis of stereoregular polyketones, polyesters, and polycarbonates . Dalton Trans. , : 4039 – 4050 .
   Google Scholar
• Chisholm , M. H. and Zhou , Z. P. 2004 . New generation polymers: the role of metal alkoxides as catalysts in the production of polyoxygenates . J. Mater. Chem. , 14 : 3081 – 3092 .
   Google Scholar
• Dechy‐Cabaret , O. , Martin‐Vaca , B. and Bourissou , D. 2004 . Controlled ring‐opening polymerization of lactide and glycolide . Chem. Rev. , 104 : 6147 – 6176 .
   PubMed Web of Science ®Google Scholar
• Wu , J. C. , Yu , T. L. , Chen , C. T. and Lin , C. C. 2006 . Recent developments in main group complexes catalyzed/initiated polymerization of lactides and related cyclic esters . Coord. Chem. Rev. , 250 : 602 – 626 .
   Web of Science ®Google Scholar
• Gross , R. A. , Kumar , A. and Kalra , B. 2001 . Polymer synthesis by in vitro enzyme catalysis . Chem. Rev. , 101 : 2097 – 2124 .
   PubMed Web of Science ®Google Scholar
• Kobayashi , S. 2006 . Enzymatic ring‐opening DOI: Polymerization of lactones by lipase catalyst: mechanistic aspects . Macromol. Symp. , 240 : 178 – 185 .
   Google Scholar
• Dubois , P. , Jacobs , C. , Jérôme , R. and Teyssié , P. 1991 . Macromolecular engineering of polylactones and polylactides. 4. Mechanism and kinetics of lactide homopolymerization by aluminum isopropoxide . Macromolecules , 24 : 2266 – 2270 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. , Berl , M. and Scharnagl , N. 1988 . Poly(lactones). 9. Polymerization mechanism of metal alkoxide initiated polymerizations of lactide and various lactones . Macromolecules , 21 : 286 – 293 .
   Web of Science ®Google Scholar
• Eguiburu , J. L. , Fernandez‐Berridi , M. J. , Cossío , F. P. and San Román , J. 1999 . Ring‐opening polymerization of L‐lactide initiated by (2‐methacryloxy)ethyloxy‐aluminum trialkoxides. 1. Kinetics . Macromolecules , 32 : 8252 – 8258 .
   Google Scholar
• Kowalski , A. , Duda , A. and Penczek , S. 2000 . Kinetics and mechanism of cyclic esters polymerization initiated with tin(II) octoate. 3. Polymerization of L,L‐dilactide . Macromolecules , 33 : 7359 – 7370 .
   Web of Science ®Google Scholar
• Marshall , E. L. , Gibson , V. C. and Rzepa , H. S. 2005 . A computational analysis of the ring‐opening polymerization of rac‐lactide initiated by single‐site beta‐diketiminate metal complexes: Defining the mechanistic pathway and the origin of stereocontrol . J. Am. Chem. Soc. , 127 : 6048 – 6051 .
   PubMed Web of Science ®Google Scholar
• Ryner , M. , Stridsberg , K. , Albertsson , A. C. , von Schenck , H. and Svensson , M. 2001 . Mechanism of ring‐opening polymerization of 1,5‐dioxepan‐2‐one and L‐lactide with stannous 2‐ethylhexanoate. A theoretical study . Macromolecules , 34 : 3877 – 3881 .
   Web of Science ®Google Scholar
• Connor , E. F. , Nyce , G. W. , Myers , M. , Mock , A. and Hedrick , J. L. 2002 . First example of N‐heterocyclic carbenes as catalysts for living polymerization: organocatalytic ring‐opening polymerization of cyclic esters . J. Am. Chem. Soc. , 124 : 914 – 915 .
   PubMed Web of Science ®Google Scholar
• Bourissou , D. , Martin‐Vaca , B. , Dumitrescu , A. , Graullier , M. and Lacombe , F. 2005 . Controlled cationic polymerization of lactide . Macromolecules , 38 : 9993 – 9998 .
   Web of Science ®Google Scholar
• Dove , A. P. , Pratt , R. C. , Lohmeijer , B. G. G. , Waymouth , R. M. and Hedrick , J. L. 2005 . Thiourea‐based bifunctional organocatalysis: Supramolecular recognition for living polymerization . J. Am. Chem. Soc. , 127 : 13798 – 13799 .
   PubMed Web of Science ®Google Scholar
• Bero , M. , Kaspercyzk , J. and Jedlinski , Z. J. 1990 . Coordination polymerization of lactides. 1. Structure determination of obtained polymers . Makromol. Chem. Macromol. Chem. Phys. , 191 : 2287 – 2296 .
   Web of Science ®Google Scholar
• Coudane , J. , Ustariz‐Peyret , C. , Schwach , G. and Vert , M. 1997 . More about the stereodependence of DD and LL pair linkages during the ring‐opening polymerization of racemic lactide . J. Polym. Sci., Polym. Chem. , 35 : 1651 – 1658 .
   Web of Science ®Google Scholar
• Spassky , N. , Simic , V. , Montaudo , M. S. and Hubert‐Pfalzgraf , L. G. 2000 . Inter‐ and intramolecular ester exchange reactions in the ring‐opening polymerization of (D L)‐lactide using lanthanide alkoxide initiators . Macromol. Chem. Phys. , 201 : 2432 – 2440 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. , Boettcher , C. and Tönnes , K. U. 1992 . Polylactones. 23. Polymerization of racemic and meso D L‐lactide with various organotin catlaysts stereochemical aspects . Polymer , 33 : 2817 – 2824 .
   Web of Science ®Google Scholar
• Chamberlain , B. M. , Cheng , M. , Moore , D. R. , Ovitt , T. M. , Lobkovsky , E. B. and Coates , G. W. 2001 . Polymerization of lactide with zinc and magnesium beta‐diiminate complexes: Stereocontrol and mechanism . J. Am. Chem. Soc. , 123 : 3229 – 3238 .
   PubMed Web of Science ®Google Scholar
• Williams , C. K. , Breyfogle , L. E. , Choi , S. K. , Nam , W. W. , Young , V. G. Jr. , Hillmyer , M. A. and Tolman , W. B. 2003 . A highly active zinc catalyst for the controlled polymerization of lactide . J. Am. Chem. Soc , 123 : 11350 – 11359 .
   Google Scholar
• Aubrecht , K. B. , Chang , K. , Hillmyer , M. A. and Tolman , W. B. 2001 . Lactide polymerization activity of alkoxide, phenoxide, and amide derivatives of yttrium(III) arylamidinates . J. Polym. Sci., Polym. Chem. , 39 : 284 – 293 .
   Google Scholar
• Kasperczyk , J. E. 1995 . Microstructure analysis of poly(lactic acid) obtained by lithium tert‐butoxide as initiator . Macromolecules , 28 : 3937 – 3939 .
   Web of Science ®Google Scholar
• Bero , M. , Dobrzynski , P. and Kasperczyk , J. 1999 . Synthesis of disyndiotactic polylactide . J. Polym. Sci., Polym. Chem. , 37 : 4038 – 4042 .
   Google Scholar
• Bhaw‐Luximon , A. , Jhurry , D. , Spassky , N. , Pensec , S. and Belleney , J. 2001 . Anionic polymerization of D,L‐lactide initiated by lithium diisopropylamide . Polymer , 42 : 9651 – 9656 .
   Google Scholar
• Xie , W. , Chen , D. , Fan , X. , Li , J. , Wang , P. G. , Cheng , H. N. and Nickol , R. G. 1999 . Lithium chloride as a catalyst for the ring‐opening polymerization of lactide in the presence of hydroxyl‐containing compounds . J. Polym. Sci., Polym. Chem. , 37 : 3486 – 3491 .
   Google Scholar
• Sipos , L. , Zsuga , M. and Kelen , T. 1992 . Living ring‐opening polymerization of L,L‐Lactide initiated with potassium tert‐butoxide and its 18‐crown‐6 complex . Polymer Bull. , 27 : 495 – 502 .
   Google Scholar
• Kricheldorf , H. R. and Boettcher , C. 1993 . Polylactones 27. Anionic‐polymerization of L‐lactide. Variation of end groups and synthesis of block‐copolymers with poly(ethylene oxide) . Makromol. Chem., Macromol. Symp. , 73 : 47 – 64 .
   Google Scholar
• Kricheldorf , H. R. and Boettcher , C. 1993 . Polylactones 26. Lithium alkoxide initiated polymerizations of L‐lactide . Makromol. Chem. , 194 : 1665 – 1669 .
   Web of Science ®Google Scholar
• Jedlinski , Z. , Walach , W. , Kurcok , P. and Adamus , G. 1991 . Polymerization of lactones, 12. Polymerization of L‐dilactide and L,D‐dilactide in the presence of potassium methoxide . Makromol. Chem. , 192 : 2051 – 2057 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. and Kreiser‐Saunders , I. 1990 . Polylactones 19. Anionic polymerization of L‐lactide in solution . Makromol. Chem. , 191 : 1057 – 1066 .
   Web of Science ®Google Scholar
• Baran , J. , Duda , A. , Kowalski , A. , Szymanski , R. and Penczek , S. 1997 . Quantitative comparison of selectivities in the polymerization of cyclic esters . Macromol. Symp. , 123 : 93 – 101 .
   Google Scholar
• Ko , B.‐T. and Lin , C.‐C. 2001 . Synthesis, characterization and catalysis of mixed‐ligand lithium aggregates, excellent initiators for the ring‐opening polymerization of L‐lactide . J. Am. Chem. Soc. , 123 : 7973 – 7977 .
   PubMed Web of Science ®Google Scholar
• Hsueh , M.‐L. , Huang , B.‐H. , Wu , J. and Lin , C.‐C. 2005 . Synthesis, characterization, and catalytic studies of lithium complexes: efficient initiators for ring‐opening polymerization of L‐lactide . Macromolecules , 38 : 9482 – 9487 .
   Google Scholar
• Chisholm , M. H. , Lin , C. C. , Gallucci , J. C. and Ko , B. T. 2003 . Binolate complexes of lithium, zinc, aluminum and titanium; preparations, structures, and studies of lactide polymerization . Dalton Trans. , : 406 – 412 .
   Google Scholar
• Schwach , G. , Coudane , J. , Engel , R. and Vert , M. 1996 . Zn lactate as initiator of DL‐lactide ring opening polymerization comparison with Sn octoate . Polymer Bull. , 37 : 771 – 776 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. and Serra , A. 1985 . Polylactones: 6. Influence of various metal salts on the optical purity of poly(L‐lactide) . Polymer Bull. , 14 : 497 – 502 .
   Web of Science ®Google Scholar
• Nijenhuis , A. J. , Grijpma , D. W. and Pennings , A. J. 1992 . Lewis acid catalyzed polymerization of L‐lactide. Kinetics and mechanism of the bulk polymerization . Macromolecules , 25 : 6419 – 6424 .
   Web of Science ®Google Scholar
• Rashkov , I. , Manolova , N. , Li , S. M. , Espartero , J. L. and Vert , M. 1996 . Synthesis, characterization, and hydrolytic degradation of PLA/PEO/PLA triblock copolymers with short poly(L‐lactic acid) chains . Macromolecules , : 50 – 56 .
   Google Scholar
• Li , S. M. , Rashkov , I. , Espartero , J. L. , Manolova , N. and Vert , M. 1996 . Synthesis, characterization, and hydrolytic degradation of PLA/PEO/PLA triblock copolymers with long poly(L‐lactic acid) blocks . Macromolecules , 29 : 57 – 62 .
   Web of Science ®Google Scholar
• Kreiser‐Saunders , I. and Kricheldorf , H. R. 1998 . Polylactones, 39. Zn lactate‐catalyzed copolymerization of L‐lactide with glycolide or epsilon‐caprolactone . Macromol. Chem. Phys. , 199 : 1081 – 1087 .
   Google Scholar
• Kricheldorf , H. R. and Damrau , D.‐O. 1998 . Polylactones 33. Polymerization of L‐lactide catalyzed by zinc amino acid salts . Macromol. Chem. Phys. , 199 : 1747 – 1752 .
   Google Scholar
• Kricheldorf , H. R. and Damrau , D.‐O. 1998 . Polylactones. 44. Polymerizations of L°‐lactide catalyzed by manganese salts . J. Mater. Sci., Pure Appl. Chem. , A35 : 1875 – 1887 .
   Google Scholar
• Kricheldorf , H. R. and Damrau , D.‐O. 1997 . Polylactones. 37. Polymerizations of L‐lactide initiated with Zn(II) L‐lactate and other resorbable Zn salts . Macromol. Chem. Phys. , 198 : 1753 – 1766 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. , Kreiser‐Saunders , I. and Damrau , D.‐O. 1999 . Resorbable initiators for polymerizations of lactones . Macromol. Symp. , 144 : 269 – 276 .
   Google Scholar
• Nijenhuis , A. J. , Grijpma , D. W. and Pennings , A. J. 1991 . Highly crystalline as polymerized poly(L‐lactide) . Polymer Bull. , 26 : 71 – 77 .
   Web of Science ®Google Scholar
• Schwach , G. , Coudane , J. , Engel , R. and Vert , M. 1998 . Ring opening polymerization of D L‐lactide in the presence of zinc metal and zinc lactate . Polymer Int. , 46 : 177 – 182 .
   Web of Science ®Google Scholar
• Zhong , Z. Y. , Ankoné , M. J. K. , Dijkstra , P. J. , Birg , C. , Westerhausen , M. and Feijen , J. 2001 . Calcium methoxide initiated ring‐opening polymerization of epsilon‐caprolactone and L‐lactide . Polymer Bull. , 46 : 51 – 57 .
   Web of Science ®Google Scholar
• Zhong , Z. Y. , Dijkstra , P. J. , Birg , C. , Westerhausen , M. and Feijen , J. 2001 . A novel and versatile calcium‐based initiating system for the ring‐opening polymerization of cyclic esters . Macromolecules , 34 : 3863 – 3868 .
   Web of Science ®Google Scholar
• Zhong , Z. Y. , Schneiderbauer , S. , Dijkstra , P. J. , Westerhausen , M. and Feijen , J. 2001 . Fast and living ring‐opening polymerization of L‐lactide initiated with in‐situ‐generated calcium alkoxides . J. Poly. Environ. , 9 : 31 – 38 .
   Web of Science ®Google Scholar
• Cheng , M. , Attygalle , A. B. , Lobkovsky , E. B. and Coates , G. W. 1999 . Single‐site catalyts for ring‐opening polymerization: synthesis of heterotactic poly(lactic acid) from rac‐lactide . J. Am. Chem. Soc , 121 : 11583 – 11584 .
   Web of Science ®Google Scholar
• Chisholm , M. H. , Huffman , J. C. and Phomphrai , K. 2001 . Monomeric metal alkoxides and trialkyl siloxides: (BDI)Mg((OBu)‐Bu‐t)(THF) and (BDI)Zn(OSiPh3)(THF). Comments on single site catalysts for ring‐opening polymerization of lactides . J. Chem. Soc. Dalton Trans. , : 222 – 224 .
   Google Scholar
• Chisholm , M. H. , Gallucci , J. and Phomphrai , K. 2002 . Coordination chemistry and reactivity of monomeric alkoxides and amides of magnesium and zinc supported by the diiminato ligand CH(CMeNC6H3–2,6‐Pr‐i(2))(2). A comparative study . Inorg. Chem. , 41 : 2785 – 2794 .
   PubMed Web of Science ®Google Scholar
• Chisholm , M. H. and Phomphrai , K. 2003 . Conformational effects in beta‐diiminate ligated magnesium and zinc amides. Solution dynamics and lactide polymerization . Inorg. Chim. Acta , 350 : 121 – 125 .
   Google Scholar
• Chisholm , M. H. , Gallucci , J. C. and Phomphrai , K. 2003 . Lactide Polymerization by well‐defined calcium coordinatioin complexes: comparisons with related magnesium and zinc chemistry . Chem. Commun. , : 48 – 49 .
   Google Scholar
• Chisholm , M. H. , Gallucci , J. C. and Phomphrai , K. 2004 . Well‐defined calcium initiators for lactide polymerization . Inorg. Chem. , 43 : 6717 – 6725 .
   PubMed Web of Science ®Google Scholar
• Hill , M. S. and Hitchcock , P. B. 2002 . Synthesis of C‐2 and C‐s symmetric zinc complexes supported by bis(phosphinimino)methyl ligands and their use in ring opening polymerisation catalysis . J. Chem. Soc. Dalton Trans. , : 4694 – 4702 .
   Google Scholar
• Hill , M. S. and Hitchcock , P. B. 2003 . Bis(phosphinimino)methyl derivatives of Ca, Sr and Ba: facile access to heavier alkaline earth organometallic chemistry . Chem. Commun. , : 1758 – 1759 .
   Google Scholar
• Dove , A. P. , Gibson , V. C. , Marshall , E. L. , White , A. J. P. and Williams , D. J. 2004 . Magnesium and zinc complexes of a potentially tridentate beta‐diketiminate ligand . Dalton Trans. , : 570 – 578 .
   Google Scholar
• Chivers , T. , Fedorchuk , C. and Parvez , M. 2005 . Synthetic and structural investigations of organomagnesium complexes of hybrid boraamidinate/amidinate ligands and their use in the polymerization of rac‐lactide . Organometallics , 24 : 580 – 586 .
   Google Scholar
• Chisholm , M. H. and Eilerts , N. W. 1996 . Single‐site metal alkoxide catalysts for ring‐opening polymerizations. Poly(dilactide) synthesis employing {HB(3‐Bu(t)pz)3}Mg(OEt) . Chem. Commun. , : 853 – 854 .
   Google Scholar
• Chisholm , M. H. , Eilerts , N. W. , Huffman , J. C. , Iyer , S. S. , Pacold , M. and Phomphrai , K. 2000 . Molecular design of single‐site metal alkoxide catalyst precursors for ring‐opening polymerization reactions leading to polyoxygenates. 1. Polylactide formation by achiral and chiral magnesium and zinc alkoxides, (eta(3)‐L)MOR, where L=trispyrazolyl‐ and trisindazolylborate ligands . J. Am. Chem. Soc , 122 : 11845 – 11854 .
   Google Scholar
• Williams , C. K. , Brooks , N. R. , Hillmyer , M. A. and Tolman , W. B. 2002 . Metalloenzyme inspired dizinc catalyst for the polymerization of lactide . Chem. Commun. , : 2132 – 2133 .
   Google Scholar
• Chisholm , M. H. , Gallucci , J. C. , Zhen , H. H. and Huffman , J. C. 2001 . Three‐coordinate zinc amide and phenoxide complexes supported by a bulky Schiff base ligand . Inorg. Chem. , 40 : 5051 – 5054 .
   PubMed Web of Science ®Google Scholar
• Chen , H. Y. , Tang , H. Y. and Lin , C. C. 2006 . Ring‐opening polymerization of lactides initiated by zinc alkoxides derived from NNO‐tridentate ligands . Macromolecules , 39 : 3745 – 3752 .
   Web of Science ®Google Scholar
• Breyfogle , L. E. , Williams , C. K. , Young , V. G. , Hillmyer , M. A. and Tolman , W. B. 2006 . Comparison of structurally analogous Zn‐2, Co‐2, and Mg‐2 catalysts for the polymerization of cyclic esters . Dalton Trans. , : 928 – 936 .
   Google Scholar
• Ejfler , J. , Kobylka , M. , Jerzykiewicz , L. B. and Sobota , P. 2005 . Highly efficient magnesium initiators for lactide polymerization . Dalton Trans. , : 2047 – 2050 .
   Google Scholar
• Lian , B. , Thomas , C. M. , Casagrande , O. L. Jr. , Lehmann , C. W. , Roisnel , T. and Carpentier , J. F. 2007 . Aluminum and zinc complexes based on amino‐bis(pyrazolyl) ligand: synthesis, structures and use in MMA and lactide polymerisation . Inorg. Chem. , 46 : 328 – 340 .
   PubMed Web of Science ®Google Scholar
• Huang , B. H. , Lin , C. N. , Hsueh , M. L. , Athar , T. and Lin , C. C. 2006 . Well‐defined sterically hindered zinc aryloxides: Excellent catalysts for ring‐opening polymerization of epsilon‐caprolactone and L‐lactide . Polymer , 47 : 6622 – 6629 .
   Google Scholar
• Bukhaltsev , E. , Frish , L. , Cohen , Y. and Vigalok , A. 2005 . Single‐site catalysis by bimetallic zinc calixarene inclusion complexes . Org. Lett. , 7 : 5123 – 5126 .
   PubMed Web of Science ®Google Scholar
• Coles , M. P. and Hitchcock , P. B. 2004 . Zinc guanidinate complexes and their application in ring‐opening polymerisation catalysis . Eur. J. Inorg. Chem. , : 2662 – 2672 .
   Google Scholar
• McClain , S. J. , Drysdale , N. E. and US , E. I. 1991 . DuPont de Nemours and Company . 5 : 028 667
   Google Scholar
• Stevels , W. M. , Ankone , M. J. K. , Dijkstra , P. J. and Feijen , J. 1996 . A versatile and highly efficient catalyst system for the preparation of polyesters based on lanthanide tris(2,6‐di‐tert‐butylphenolate)s and various alcohols . Macromolecules , 29 : 3332 – 3333 .
   Web of Science ®Google Scholar
• Stevels , W. M. , Ankone , M. J. K. , Dijkstra , P. J. and Feijen , J. 1996 . Kinetics and mechanism of L‐lactide polymerization using two different yttrium alkoxides as initiators . Macromolecules , 29 : 6132 – 6138 .
   Web of Science ®Google Scholar
• Simic , V. , Spassky , N. and Hubert‐Pfalzgraf , L. G. 1997 . Ring‐opening polymerization of D L‐ lactide using rare‐earth mu‐oxo isopropoxides as initiator systems . Macromolecules , 30 : 7338 – 7340 .
   Google Scholar
• Simic , V. , Girardon , V. , Spassky , N. , Hubert‐Pfalzfraf , L. G. and Duda , A. 1998 . Ring‐opening polymerization of lactides initiated with yttrium tris‐isopropoxyethoxide . Polym. Degr. Stab. , 59 : 227 – 229 .
   Google Scholar
• Stevels , W. M. , Ankone , M. J. K. , Dijkstra , P. J. and Feijen , J. 1995 . Well defined block copolymers of epsilon‐caprolactone and L‐lactide using Y‐5(mu‐O)(OiPr)13 as an initiator . Macromol. Chem. Phys. , 196 : 1153 – 1161 .
   Web of Science ®Google Scholar
• McClain , S. J. , Ford , T. M. and Drysdale , N. E. 1992 . Living ring‐opening polymerization of (L,L)‐lactide by yttrium and lanthanum alkoxides . Polym. Prep. , : 463 – 464 .
   Google Scholar
• Chamberlain , B. M. , Sun , Y. , Hagadorn , J. R. , Hemmesch , E. W. , Young , V. G. Jr. , Pink , M. , Hillmyer , M. A. and Tolman , W. B. 1999 . Discrete yttrium(III) complexes as lactide polymerization complexes . Macromolecules , 32 : 2400 – 2402 .
   Google Scholar
• Chamberlain , B. M. , Jazdzewski , B. A. , Pink , M. , Hillmyer , M. A. and Tolman , W. B. 2000 . Controlled polymerization of D,L‐lactide and epsilon‐caprolactone by structurally well‐defined alkoxo‐bridged di‐ and triyttrium(III) complexes . Macromolecules , 33 : 3970 – 3977 .
   Google Scholar
• Ovitt , T. M. and Coates , G. W. 1999 . Stereoselective ring‐opening polymerization of meso‐lactide; Synthesis of syndiotactic polyl(lactic acid) . J. Am. Chem. Soc , 121 : 4072 – 4073 .
   Web of Science ®Google Scholar
• Ovitt , T. M. and Coates , G. W. 2002 . Stereochemistry of lactide polymerization with chiral catalysts: new opportunities for stereocontrol using polymer exchange mechanisms . J. Am. Chem. Soc , 124 : 1316 – 1326 .
   PubMed Web of Science ®Google Scholar
• Ma , H. , Spaniol , T. P. and Okuda , J. 2003 . Rare earth metal supported 1, omega‐dithiaalkanediyl‐bridged bis(phenolato) ligands: synthesis, characterization and ring‐opening polymerization catalysis of L‐lactide . Dalton Trans. , : 4770 – 4780 .
   Google Scholar
• Ma , H. , Spaniol , T. P. and Okuda , J. 2006 . Highly heteroselective ring‐opening polymerization of rac‐lactide initiated by bis(phenolato)scandium complexes . Angew. Chem. Int. Ed. , 45 : 7818 – 7821 .
   Google Scholar
• Ma , H. and Okuda , J. 2005 . Kinetics and mechanism of L‐lactide polymerization by rare earth metal silylamido complexes: effect of alcohol addition . Macromolecules , 38 : 2665 – 2673 .
   Google Scholar
• Cai , C. X. , Amgoune , A. , Lehmann , C. W. and Carpentier , J. F. 2004 . Stereoselective ring‐opening polymerization of racemic lactide using alkoxy‐amino‐bis(phenolate) group 3 metal complexes . Chem. Commun. , : 330 – 331 .
   Google Scholar
• Amgoune , A. , Thomas , C. M. , Roisnel , T. and Carpentier , J. F. 2006 . Ring‐opening polymerization of lactide with group 3 metal complexes supported by dianionic alkoxy‐amino‐bisphenolate ligands: combining high activity, productivity, and selectivity . Chem. Eur. J. , 12 : 169 – 179 .
   Web of Science ®Google Scholar
• Hodgson , L. M. , White , A. J. P. and Williams , C. K. 2006 . Yttrium(III) complex as a highly active catalyst for lactide polymerization . J. Polym. Sci., Polym. Chem. , 44 : 6646 – 6651 .
   Google Scholar
• Westmoreland , I. and Arnold , J. 2006 . Phenoxytriamine complexes of yttrium: synthesis, structure and use in the polymerization of lactide and epsilon‐caprolactone . Dalton Trans. , : 4155 – 4163 .
   Google Scholar
• Alaaeddine , A. , Amgoune , A. , Thomas , C. M. , Dagorne , S. , Bellemin‐Laponnaz , S. and Carpentier , J.‐F. 2006 . Bis[bis(oxazolinato)] complexes of yttrium and lanthanum: molecular structure and use in polymerization of DL‐lactide and DL‐beta‐butyrolactone . Eur. J. Inorg. Chem. , : 3652 – 3658 .
   Google Scholar
• Kim , Y. , Jnaneshwara , G. K. and Verkade , J. G. 2003 . Titanium alkoxides as initiators for the controlled polymerization of lactide . Inorg. Chem. , 42 : 1437 – 1447 .
   PubMed Web of Science ®Google Scholar
• Kim , Y. and Verkade , J. G. 2002 . A tetrameric titanium alkoxide as a lactide polymerization catalyst . Macromol. Rapid Commun. , 23 : 917 – 921 .
   Web of Science ®Google Scholar
• Kim , Y. and Verkade , J. G. 2002 . Novel titanatranes with different ring sizes: syntheses, structures and lactide polymerization catalytic capabilities . Organometallics , 21 : 2395 – 2399 .
   Web of Science ®Google Scholar
• Kim , Y. and Verkade , J. G. 2005 . Living polymerization of lactide usign titanium alkoxide catalysts . Macromol. Symp. , 224 : 105 – 117 .
   Google Scholar
• Gregson , C. K. , Blackmore , I. J. , Gibson , V. C. , Long , N. J. , Marshall , E. L. and White , A. J. P. 2006 . Titanium‐salen complexes as initiators for the ring opening polymerisation of rac‐lactide . Dalton Trans. , : 3134 – 3140 .
   Google Scholar
• Gregson , C. K. A. , Gibson , V. C. , Long , N. J. , Marshall , E. L. , Oxford , P. J. and White , A. J. P. 2006 . Redox control within single‐site polymerization catalysts . J. Am. Chem. Soc. , 128 : 7410 – 7411 .
   Google Scholar
• Chmura , A. J. , Davidson , M. G. , Jones , M. D. , Lunn , M. D. , Mahon , M. F. , Johnson , A. F. , Khunkamchoo , P. , Roberts , S. L. and Wong , S. S. F. 2006 . Group 4 complexes with aminebisphenolate ligands and their application for the ring opening polymerization of cyclic esters . Macromolecules , 39 : 7250 – 7257 .
   Google Scholar
• Gendler , S. , Segal , S. , Goldberg , I. , Goldschmidt , Z. and Kol , M. 2006 . Titanium and zirconium complexes of dianionic and trianionic amine‐phenolate‐type ligands in catalysis of lactide polymerization . Inorg. Chem. , 45 : 4783 – 4790 .
   PubMed Web of Science ®Google Scholar
• Russell , S. K. , Gamble , C. L. , Gibbins , K. J. , Juhl , K. C. S. , Mitchell , W. S. III , Tumas , A. J. and Hofmeister , G. E. 2005 . Stereoselective controlled polymerization of DL‐lactide with [Ti(trisphenolate)O‐i‐Pr](2) initiators . Macromolecules , 38 : 10336 – 10340 .
   Web of Science ®Google Scholar
• Takashima , Y. , Nakayama , Y. , Watanabe , K. , Itono , T. , Ueyama , N. , Nakamura , A. , Yasuda , H. , Harada , A. and Okuda , J. 2002 . Polymerizations of cyclic esters catalyzed by titanium complexes having chalcogen‐bridged chelating diaryloxo ligands . Macromolecules , 35 : 7538 – 7544 .
   Web of Science ®Google Scholar
• Stolt , M. and Södergård , A. 1999 . Use of monocarboxylic iron derivatives in the ring‐opening polymerization of L‐lactide . Macromolecules. , 32 : 6412 – 6417 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. and Boettcher , C. 1993 . Polylactones 21. Polymerization of L,L‐lactide and rac‐D,L‐lactide with hematin and related porphyrin complexes . Makromol. Chem. , 194 : 463 – 473 .
   Google Scholar
• Kricheldorf , H. R. and Damrau , D.‐O. 1997 . Polylactones 38. Polymerization of L‐lactide with Fe(II) lactate and other resorbable Fe(II) salts . Macromol. Chem. Phys. , 198 : 1767 – 1774 .
   Google Scholar
• Södergård , A. and Stolt , M. 1998 . Ring‐opening polymerization of L‐lactide by means of different iron compounds . Macromol. Symp. , 130 : 393 – 402 .
   Google Scholar
• Gorczynski , J. L. , Chen , J. B. and Fraser , C. L. 2005 . Iron tris(dibenzoylmethane)‐centered polylactide stars: multiple roles for the metal complex in lactide ring‐opening polymerization . J. Am. Chem. Soc. , 127 : 14956 – 14957 .
   Google Scholar
• Wang , X. Y. , Liao , K. R. , Quan , D. P. and Wu , Q. 2005 . Bulk ring‐opening polymerization of lactides initiated by ferric alkoxides . Macromolecules , 38 : 4611 – 4617 .
   Web of Science ®Google Scholar
• McGuinness , D. S. , Marshall , E. L. , Gibson , V. C. and Steed , J. W. 2003 . Anionic Iron(II) alkoxides as initiators for the controlled ring‐opening polymerization of lactide . J. Polym. Sci., Polym. Chem. , 41 : 3798 – 3803 .
   Web of Science ®Google Scholar
• O'Keefe , B. J. , Monnier , S. M. , Hillmyer , M. A. and Tolman , W. B. 2001 . Rapid and controlled polymerization of lactide by structurally characterized ferric alkoxides . J. Am. Chem. Soc. , 123 : 339 – 340 .
   Google Scholar
• O'Keefe , B. J. , Breyfogle , L. E. , Hillmyer , M. A. and Tolman , W. B. 2002 . Mechanistic comparison of cyclic ester polymerizations by novel iron(III)‐alkoxide complexes: single vs multiple site catalysis . J. Am. Chem. Soc. , 124 : 4384 – 4393 .
   Google Scholar
• Gibson , V. C. , Marshall , E. L. , Navarro‐Llobet , D. , White , A. J. P. and Williams , D. J. 2002 . A well‐defined iron(II) alkoxide initiator for the controlled polymerization of lactide . J. Chem. Soc. Dalton Trans. , : 4321 – 4322 .
   Google Scholar
• Penczek , S. , Syzmanski , R. and Duda , A. 1995 . Polymerizations with contribution of covalent and ionic species . Macromol. Symp. , 98 : 193 – 216 .
   Google Scholar
• Kowalski , A. , Duda , A. and Penczek , S. 1998 . Polymerization of L,L‐lactide initiated by aluminum isopropoxide trimer or tetramer . Macromolecules , 31 : 2114 – 2122 .
   Web of Science ®Google Scholar
• Ropson , N. , Dubois , P. , Jérôme , R. and Teyssié , P. 1995 . Macromolecular engineering of polylactones and polylactides. 20. Effect of monomer, solvent and initiator on the ring‐opening polymerization as initiated with aluminum alkoxides . Macromolecules , 28 : 7589 – 7598 .
   Google Scholar
• Degeé , P. , Dubois , P. and Jérôme , R. 1997 . Bulk polymerization of lactides initiated by aluminum isopropoxide, 2. Beneficial effect of Lewis bases and transfer agents . Macromol. Chem. Phys. , 198 : 1973 – 1984 .
   Google Scholar
• Dubois , P. , Jérôme , R. and Teyssié , P. 1993 . Macromolecular engineering of polylactones and polylactides. 10. Selective end‐functionalisation of poly(D,L)‐lactide . J. Polym. Sci., Polym. Chem. , 31 : 505 – 514 .
   Google Scholar
• Kricheldorf , H. R. and Kreiser‐Saunders , I. 1994 . Polylactones: 30. Vitamins, hormones and drugs as co‐initiators of AlEt(3)‐initiated polymerizations of lactide . Polymer , 35 : 4175 – 4180 .
   Web of Science ®Google Scholar
• Kunioka , M. , Wang , Y. and Onozawa , S. Y. 2005 . Poly(lactic acid) polymerized by aluminum triflate . Macromol. Symp. , 224 : 167 – 179 .
   Google Scholar
• Le Borgne , A. , Vincens , V. , Jouglard , M. and Spassky , N. 1993 . Ring‐opening oligomerization reactions using aluminum complexes of schiff‐bases as initiators . Makromol. Chem., Macromol. Symp. , 73 : 37 – 46 .
   Google Scholar
• Montaudo , G. , Montaudo , M. S. , Puglisi , C. , Samperi , F. , Spassky , N. , Le Borgne , A. and Wisniewski , M. 1996 . Evidence for ester‐exchange reactions and cyclic oligomer formation in the ring‐opening polymerization of lactide with aluminum complex initiators . Macromolecules , 29 : 6461 – 6465 .
   Web of Science ®Google Scholar
• Spassky , N. , Wisniewski , M. , Pluta , C. and Le Borgne , A. 1996 . Highly stereoelective polymerization of rac‐(D,L)‐lactide with a chiral Schiff's base/aluminum alkoxide initiator . Macromol. Chem. Phys. , 197 : 2627 – 2637 .
   Web of Science ®Google Scholar
• Bhaw‐Luximon , A. , Jhurry , D. and Spassky , N. 2000 . Controlled polymerization of DL‐lactide using a Schiff's base al‐alkoxide initiator derived from 2‐hydroxyacetophenone . Polymer Bull. , 44 : 31 – 38 .
   Web of Science ®Google Scholar
• Jhurry , D. , Bhaw‐Luximon , A. and Spassky , N. 2001 . Synthesis of polylactides by new aluminum schoff's base complexes . Macromol. Symp. , 175 : 67 – 79 .
   Web of Science ®Google Scholar
• Radano , C. P. , Baker , G. L. and Smith , M. R. 2000 . Stereoselective polymerization of a racemic monomer with a racemic catalyst: direct preparation of the polylactic acid stereocomplex from racemic lactide . J. Am. Chem. Soc , 122 : 1552 – 1553 .
   Web of Science ®Google Scholar
• Ovitt , T. M. and Coates , G. W. 2000 . Stereoselective ring‐opening polymerization of rac‐lactide with a single‐site, racemic aluminum alkoxide catalyst: synthesis of stereoblock poly(lactic acid) . J. Polym. Sci., Polym. Chem. , 38 : 4686 – 4692 .
   Web of Science ®Google Scholar
• Zhong , Z. Y. , Dijkstra , P. J. and Feijen , J. 2002 . [(salen)Al]‐mediated, controlled and stereoselective ring‐opening polymerization of lactide in solution and without solvent: synthesis of highly isotactic polylactide stereocopolymers from racemic D,L‐lactide . Angew. Chem. Int. Ed. , 41 : 4510 – 4513 .
   PubMed Web of Science ®Google Scholar
• Zhong , Z. Y. , Dijkstra , P. J. and Feijen , J. 2003 . Controlled and stereoselective polymerization of lactide: kinetics, selectivity, and microstructures . J. Am. Chem. Soc , 125 : 11291 – 11298 .
   PubMed Web of Science ®Google Scholar
• Chisholm , M. H. , Patmore , N. J. and Zhou , Z. P. 2005 . Concerning the relative importance of enantiomorphic site vs. chain end control in the stereoselective polymerization of lactides: reactions of (R,R‐salen)‐ and (S,S‐salen)‐aluminum alkoxides LAlOCH2R complexes (R=CH3 and S‐CHMeCl) . Chem. Commun. , : 127 – 129 .
   Google Scholar
• Cameron , P. A. , Jhurry , D. , Gibson , V. C. , White , A. J. P. , Williams , D. J. and Williams , S. 1999 . Controlled polymerization of lactides at ambient temperature using [5‐Cl‐salen]AlOMe . Macromol. Rapid Commun. , 20 : 616 – 618 .
   Web of Science ®Google Scholar
• Nomura , N. , Ishii , R. , Akakura , M. and Aoi , K. 2002 . Stereoselective ring‐opening polymerization of racemic lactide using aluminum‐achiral ligand complexes: exploration of a chain‐end control mechanism . J. Am. Chem. Soc , 124 : 5938 – 5939 .
   PubMed Web of Science ®Google Scholar
• Tang , Z. H. , Chen , X. S. , Pang , X. , Yang , Y. K. , Zhang , Z. F. and Jing , X. B. 2004 . Stereoselective polymerization of rac‐lactide using a monoethylaluminium Schiff base complex . Biomacromolecules , 5 : 965 – 970 .
   PubMed Web of Science ®Google Scholar
• Tang , Z. H. , Chen , X. S. , Yang , Y. K. , Pang , X. , Sun , J. R. , Zhang , X. F. and Jing , X. B. 2004 . Stereoselective polymerization of rac‐lactide with a bulky aluminum/Schiff base complex . J. Polym. Sci., Polym. Chem. , 42 : 5974 – 5982 .
   Web of Science ®Google Scholar
• Hormnirun , P. , Marshall , E. L. , Gibson , V. C. , Pugh , R. I. and White , A. J. P. 2006 . Study of ligand substituent effects on the rate and stereoselectivity of lactide polymerization using aluminum salen‐type initiators . PNAS , 103 : 15343 – 15348 .
   Google Scholar
• Du , H. , Pang , X. , Yu , H. Y. , Zhuang , X. L. , Chen , X. S. , Cui , D. M. , Wang , X. H. and Jing , X. B. 2007 . Polymerization of rac‐lactide using schiff base aluminum catalysts: structure, activity, and stereoselectivity . Macromolecules , 40 : 1904 – 1913 .
   Web of Science ®Google Scholar
• Tang , Z. , Yang , Y. , Pang , X. , Hu , J. , Chen , X. , Hu , N. and Jing , X. 2005 . Controlled and stereospecific polymerization of rac‐lactide with a single site ethyl aluminum and alcohol initiating system . J. App. Polym. Sci. , 98 : 102 – 108 .
   Web of Science ®Google Scholar
• Trofimoff , L. , Aida , T. and Inoue , S. 1987 . Formation of poly(lactide) with controlled molecular weight. Polymerization of lactide by aluminum porphyrin . Chem. Lett. , : 991 – 994 .
   Google Scholar
• Emig , N. , Nguyen , H. , Krautscheid , H. , Reau , R. , Cazaux , J. B. and Bertrand , G. 1998 . Neutral and cationic tetracoordinated aluminum complexes featuring tridentate nitrogen donors: synthesis, structure, and catalytic activity for the ring‐opening polymerization of propylene oxide and (D,L)‐lactide . Organometallics , 17 : 3599 – 3608 .
   Web of Science ®Google Scholar
• Huang , C. H. , Wang , F. C. , Ko , B. T. , Yu , T. L. and Lin , C. C. 2001 . Ring‐opening polymerization of epsilon‐caprolactone and L‐Lactide using aluminum thiolates as initiator . Macromolecules , 34 : 356 – 361 .
   Web of Science ®Google Scholar
• Liu , Y. C. , Ko , B. T. and Lin , C. C. 2001 . A highly efficient catalyst for the “living” and “immortal” polymerization of epsilon‐caprolactone and L‐lactide . Macromolecules , 34 : 6196 – 6201 .
   Web of Science ®Google Scholar
• Li , H. , Wang , C. H. , Bai , F. , Yue , J. and Woo , H. G. 2004 . Living ring‐opening polymerization of L‐lactide catalyzed by Red‐Al . Organometallics , 23 : 1411 – 1415 .
   Google Scholar
• Doherty , S. , Errington , R. J. , Housley , N. and Clegg , W. 2004 . Dimeric aluminum chloride compelxes of N‐alkoxyalkyl‐beta‐ketoimines: activation with propylene oxide to form efficient lactide polymerization catalysts . Organometallics , 23 : 2382 – 2388 .
   Web of Science ®Google Scholar
• Hormnirun , P. , Marshall , E. L. , Gibson , V. C. , White , A. J. P. and Williams , D. J. 2004 . Remarkable stereocontrol in the polymerization of racemic lactide using aluminum initiators supported by tetradentate aminophenoxide ligands . J. Am. Chem. Soc , 126 : 2688 – 2689 .
   PubMed Web of Science ®Google Scholar
• Pang , X. , Du , H. , Chen , X. , Zhuang , X. , Cui , D. and Jing , X. 2005 . Aluminum Schiff base catalysts derived from beta‐diketone for the stereoselective polymerization of racemic lactides . J. Polym. Sci., Polym. Chem. , 43 : 6605 – 6612 .
   Web of Science ®Google Scholar
• Ma , H. Y. , Melillo , G. , Oliva , L. , Spaniol , T. P. , Englert , U. and Okuda , J. 2005 . Aluminum alkyl complexes supported by [OSSO] type bisphenolato ligands: synthesis, characterization and living polymerization of rac‐lactide . Dalton Trans. , : 721 – 727 .
   Google Scholar
• Schwach , G. , Coudane , J. , Engel , R. and Vert , M. 1997 . More about the polymerization of lactides in the presence of stannous octoate . J. Polym. Sci., Polym. Chem. , 35 : 3431 – 3440 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. , Kreiser‐Saunders , I. and Stricker , A. 2000 . Polylactones 48. SnOct(2)‐initiated polymerizations of lactide: a mechanistic study . Macromolecules , 33 : 702 – 709 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. 2000 . Tin‐initiated polymerizations of lactones: mechanistic and preparative aspects . Macromol. Symp. , 153 : 55 – 65 .
   Google Scholar
• Duda , A. , Penczek , S. , Kowalski , A. and Libiszowski , J. 2000 . Polymerizations of epsilon‐caprolactone and L,L‐dilactide initiated with stannous octoate and stannous butoxide ‐ A comparison . Macromol. Symp. , 153 : 41 – 53 .
   Google Scholar
• Penczek , S. , Duda , A. , Kowalski , A. , Libiszowski , J. , Majerska , K. and Biela , T. 2000 . On the mechanism of polymerization of cyclic esters induced by tin(II) octoate . Macromol. Symp. , 157 : 61 – 70 .
   Google Scholar
• Kowalski , A. , Libiszowski , J. , Duda , A. and Penczek , S. 2000 . Polymerization of L,L‐lactide initiated by tin(II) butoxide . Macromolecules , 33 : 1964 – 1971 .
   Web of Science ®Google Scholar
• Dove , A. P. , Gibson , V. C. , Marshall , E. L. , White , A. J. P. and Williams , D. J. 2001 . A well defined tin(II) initiator for the living polymerization of lactide . Chem. Commun. , : 283 – 284 .
   Google Scholar
• Dove , A. P. , Gibson , V. C. , Marshall , E. L. , Rzepa , H. S. , White , A. J. P. and Williams , D. J. 2006 . Synthetic, structural, mechanistic, and computational studies on single‐site beta‐diketiminate tin(II) initiators for the polymerization of rac‐lactide . J. Am. Chem. Soc. , 128 : 9834 – 9843 .
   PubMed Web of Science ®Google Scholar
• Aubrecht , K. B. , Hillmyer , M. A. and Tolman , W. B. 2002 . Polymerization of lactide by monomeric Sn(II) alkoxide complexes . Macromolecules , 35 : 644 – 650 .
   Web of Science ®Google Scholar
• Chisholm , M. H. and Delbridge , E. E. 2001 . Ring‐opening of lactides and related cyclic monomers by triaryltin(IV) alkoxides and amides . Chem. Commun. , : 1308 – 1309 .
   Google Scholar
• Chisholm , M. H. and Delbridge , E. E. 2003 . A study of the ring‐opening polymerization (ROP) of L‐lactide by Ph2SnX2 precursors (X=NMe2, OiPr): the notable influence of initiator group . New J. Chem. , 27 : 1177 – 1183 .
   Google Scholar
• Chisholm , M. H. , Delbridge , E. E. and Gallucci , J. C. 2004 . Modelling the catalyst resting state in aryl tin(IV) polymerizations of lactide and estimating the relative rates of transamidation, transesterification and chain transfer . New J. Chem. , 28 : 145 – 152 .
   Google Scholar
• Kricheldorf , H. R. , Lee , S.‐R. and Bush , S. 1996 . Polylactones 36. Macrocyclic polymerization of lactides with cyclic Bu(2)Sn initiators derived from 1,2‐ethanediol, 2‐mercaptoethanol and 1,2‐dimercaptoethane . Macromolecules , 29 : 1375 – 1381 .
   Web of Science ®Google Scholar
• Stridsberg , K. , Ryner , M. and Albertsson , A.‐C. 2000 . Dihydroxy‐terminated poly(L‐Lactide) obtained by controlled ring‐opening polymerization: investigation of the polymerization mechanism . Macromolecules , 33 : 2862 – 2869 .
   Web of Science ®Google Scholar
• Ryner , M. , Finne , A. , Albertsson , A.‐C. and Kricheldorf , H. R. 2001 . L‐Lactide macromonomer synthesis initiated by new cyclic tin alkoxides functionalized for brushlike structures . Macromolecules , 34 : 7281 – 7287 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. 2002 . Syntheses of biodegradable (multi) block copolymers, star‐shaped polyesters and networks via ring‐expansion polymerization . Polym. Adv. Technol. , 13 : 969 – 974 .
   Google Scholar
• Kricheldorf , H. R. and Dunsing , R. 1986 . Polylactones 8. Mechanism of the cationic polymerization of L,L‐dilactide . Makromol. Chem. , 187 : 1611 – 1625 .
   Web of Science ®Google Scholar
• Kricheldorf , H. R. and Kreiser‐Saunders , I. 1987 . Polylactones 11. Cationic copolymerization f glycolide with L,L‐dilactide . Makromol. Chem. , 188 : 1861 – 1873 .
   Web of Science ®Google Scholar
• Nederberg , F. , Connor , E. F. , Moller , M. , Glauser , T. and Hedrick , J. L. 2001 . New paradigms for organic catalysts: the first organocatalytic living polymerization . Angew. Chem. Int. Ed. , 40 : 2712 – 2715 .
   Web of Science ®Google Scholar
• Myers , M. , Connor , E. F. , Glauser , T. , Mock , A. , Nyce , G. W. and Hedrick , J. L. 2002 . Phosphines:nucleophilic organic catalysts for the controlled ring‐opening polymerization of lactides . J. Polym. Sci., Polym. Chem. , 40 : 844 – 851 .
   Google Scholar
• Nyce , G. W. , Glauser , T. , Connor , E. F. , Mock , A. , Waymouth , R. M. and Hedrick , J. L. 2003 . In situ generation of carbenes: a general and versatile platform for organocatalytic living polymerisation . J. Am. Chem. Soc , 125 : 3046 – 3056 .
   Google Scholar
• Nyce , G. W. , Csihony , S. , Waymouth , R. M. and Hedrick , J. L. 2004 . A general and versatile approach to thermally generated N‐heterocyclic carbenes . Chem. Eur. J. , 10 : 4073 – 4079 .
   Google Scholar
• Coulembier , O. , Dove , A. R. , Pratt , R. C. , Sentman , A. C. , Culkin , D. A. , Mespouille , L. , Dubois , P. , Waymouth , R. M. and Hedrick , J. L. 2005 . Latent, thermally activated organic catalysts for the on‐demand living polymerization of lactide . Angew. Chem. Int. Ed. , 44 : 4964 – 4968 .
   Google Scholar
• Csihony , S. , Culkin , D. A. , Sentman , A. C. , Dove , A. P. , Waymouth , R. M. and Hedrick , J. L. 2005 . Single‐component catalysts/initiators for the organocatalytic ring‐opening polymerisation of lactide . J. Am. Chem. Soc , 127 : 9079 – 9084 .
   Google Scholar
• Coulembier , O. , Lohmeijer , B. G. G. , Dove , A. P. , Pratt , R. C. , Mespouille , L. , Culkin , D. A. , Benight , S. J. , Dubois , P. , Waymouth , R. M. and Hedrick , J. L. 2006 . Alcohol adducts of N‐heterocyclic carbenes: Latent catalysts for the thermally‐controlled living polymerization of cyclic esters . Macromolecules , 39 : 5617 – 5628 .
   Google Scholar
• Pratt , R. C. , Lohmeijer , B. G. G. , Long , D. A. , Lundberg , P. N. P. , Dove , A. P. , Li , H. B. , Wade , C. G. , Waymouth , R. M. and Hedrick , J. L. 2006 . Exploration, optimization, and application of supramolecular thiourea‐amine catalysts for the synthesis of lactide (co)polymers . Macromolecules , 39 : 7863 – 7871 .
   Google Scholar
• Lohmeijer , B. G. G. , Pratt , R. C. , Leibfarth , F. , Logan , J. W. , Long , D. A. , Dove , A. P. , Nederberg , F. , Choi , J. , Wade , C. , Waymouth , R. M. and Hedrick , J. L. 2006 . Guanidine and amidine organocatalysts for ring‐opening polymerization of cyclic esters . Macromolecules , 39 : 8574 – 8583 .
   Google Scholar
• Dove , A. P. , Pratt , R. C. , Lohmeijer , B. G. G. , Culkin , D. A. , Hagberg , E. C. , Nyce , G. W. , Waymouth , R. M. and Hedrick , J. L. 2006 . N‐Heterocyclic carbenes: effective organic catalysts for living polymerization . Polymer , 47 : 4018 – 4025 .
   Google Scholar
• Pratt , R. C. , Lohmeijer , B. G. G. , Long , D. A. , Waymouth , R. M. and Hedrick , J. L. 2006 . Triazacyclodecene: a simple bifunctional organocatalyst for acyl transfer and ring opening polymerization of cyclic esters . J. Am. Chem. Soc , 128 : 4556 – 4557 .
   PubMed Web of Science ®Google Scholar
• Jensen , T. R. , Breyfogle , L. E. , Hillmyer , M. A. and Tolman , W. B. 2004 . Stereoselective polymerization of D,L‐lactide using N‐heterocyclic carbene based compounds . Chem. Commun. , : 2504 – 2505 .
   Google Scholar
• Zhong , Z. Y. , Schneiderbauer , S. , Dijkstra , P. J. , Westerhausen , M. and Feijen , J. 2003 . Single‐site calcium initiators for the controlled ring‐opening polymerization of lactides and lactones . Polymer Bull. , 51 : 175 – 182 .
   Web of Science ®Google Scholar
• Geisbrecht , G. R. , Whitener , G. D. and Arnold , J. 2001 . Mono‐guanidinate complexes of lanthanum: synthesis, structure and their use in lactide polymerization . Dalton Trans. , : 923 – 927 .
   Google Scholar
• Beckerle , K. , Hultzsch , K. C. and Okuda , J. 1999 . Ring‐opening polymerization of lactides using heterobimetallic yttrocene complexes . Macromol. Chem. Phys. , 200 : 1702 – 1707 .
   Google Scholar
• Chuck , C. J. , Davidson , M. G. , Jones , M. D. , Kociok‐Köhn , G. , Lunn , M. D. and Wu , S. 2006 . Air‐stable titanium alkoxide based metal‐organic framework as an initiator for ring‐opening polymerization of cyclic esters . Inorg. Chem. , 45 : 6595 – 6597 .
   Google Scholar
• Gornshtein , F. , Kapon , M. , Botoshansky , M. and Eisen , M. S. 2007 . Titanium and zirconium complexes for polymerization of propylene and cyclic esters . Organometallics , 26 : 497 – 507 .
   Google Scholar
• Atkinson , R. J. , Gerry , K. , Gibson , V. C. , Long , N. J. , Marshall , E. L. and West , L. J. 2007 . Synthesis of 1,1'‐ferrocenediyl salicylaldimine ligands and their application in titanium‐initiated lactide polymerization . Organometallics , 26 : 316 – 320 .
   Google Scholar
• Sun , J. , Shi , W. , Chen , D. and Liang , C. 2002 . The ring‐opening polymerization of D,L‐lactide catalyzed by new complexes of Cu, Zn, Co and Ni Schiff base derived from salicylidene and L‐aspartic acid . J. App. Polym. Sci. , 48 : 3312 – 3315 .
   Google Scholar
• Majerska , K. and Duda , A. 2004 . Stereocontrolled polymerization of racemic lactide with chiral initiator: combining stereoelection and chiral ligand‐exchange mechanism . J. Am. Chem. Soc , 126 : 1026 – 1027 .
   PubMed Web of Science ®Google Scholar
• Tang , Z. H. and Gibson , V. C. 2007 . rac‐Lactide polymerization using aluminum complexes bearing tetradentate phenoxy‐amine ligands . Eur. Polym. J. , 43 : 150 – 155 .
   Web of Science ®Google Scholar