Approach to Synthesis of β-Enamino Ketones and Pyrroles Catalyzed by Gallium(III) Triflate Under Solvent-Free Conditions

REFERENCES

• (a) Yamamoto , H. (Ed). Lewis Acids in Organic Synthesis ; Wiley : Weinheim , 2000 ; vols. 1 and 2 ; (b) Pons , J. M. ; Santelli , M. (Eds.). Lewis Acids and Selectivity in Organic Synthesis ; CRC : Boca Raton , Fl ., 1995 ; (c) Schinzer , D. Selectivities in Lewis Acid Promoted Reactions , Kluwer : Dordrecht , 1989 .
   Google Scholar
• Kobayashi , S. ; Sugiura , M. ; Kitagawa , H. ; Lam , W. L. Rare-earth metal triflates in organic synthesis . Chem. Rev. 2002 , 102 , 2227 .
   PubMed Web of Science ®Google Scholar
• Forsberg , J. H. ; Spaziano , V. T. ; Balasubramanian , T. M. ; Liu , G. K. ; Kinsley , S. A. ; Duckworth , C. A. ; Poteruca , J. J. ; Brown , P. S. ; Miller , J. L. Use of lanthanide(III) ions as catalysts for the reactions of amines with nitriles . J. Org. Chem. 1987 , 52 , 1017 .
   Web of Science ®Google Scholar
• (a) Rappoport , Z. The Chemistry of Enamines ; Wiley : New York , 1994 ; part 1; (b) Sweeney , T. R. ; Strube , R. E. Burger's Medicinal Chemistry ; Wiley : New York , 1979 ; part 2 , p. 333 ; (c) Foster, J. E.; Nicholson, J. M.; Butcher, R.; Stables, J. P.; Edafiogho, I. O.; Goodwin, A. M.; Henson, M. C.; Smith, C. A.; Scott, K. R. Synthesis, characterization, and anticonvulsant activity of enaminones, part 6: Synthesis of substituted vinylic benzamides as potential anticonvulsants. Bioorg. Med. Chem. 1999, 7, 2415; (d) Spivey, A. C.; Srikaran, R.; Diaper, C. M.; Turner, D. J. Traceless solid phase synthesis of 2-substituted pyrimidines using an “off-the-shelf” chlorogermane-functionalised resin. Org. Biomol. Chem. 2003, 1, 1638; (e) Bartoli, G.; Cimarelli, C.; Marcantoni, E.; Palmieri, G.; Petrini, M. Chemo- and diastereoselective reduction of β-enamino esters: A convenient synthesis of both cis- and trans-γ-amino alcohols and β-amino esters. J. Org. Chem. 1994, 59, 5328; (f) Ferraz, H. M. C.; Pereira, F. L. C.; Leite, F. S.; Nuns, M. R. S.; Payret-Arrua, M. E. Synthesis of N-substituted pyrrole and tetrahydroindole derivatives from alkenyl β-dicarbonyl compounds. Tetrahedron 1999, 55, 10915; (g) Reddy, G. J.; Latha, D.; Thirupathaiah, C.; Rao, K. S. A facile synthesis of 2,3-disubstituted-6-arylpyridines from enaminones using montmorillonite K10 as solid acid support. Tetrahedron Lett. 2005, 46, 301 .
   Google Scholar
• (a) Hannick , S. M. ; Kishi , Y. An improved procedure for the Blaise reaction: A short, practical route to the key intermediates of the saxitoxin synthesis. J. Org. Chem. 1983, 48, 3833; (b) Jiang , N. ; Qu , Z. ; Wang , J. 1,2-Aryl and 1,2-hydride migration in transition metal complex catalyzed diazo decomposition: A novel approach to α-aryl-β-enamino esters. Org. Lett. 2001, 3, 2989; (c) Cimarelli , G. ; Palmieri , G. ; Volpini , E. The reaction of β-enaminoesters with organolithium reagents: A convenient method for the regioselective synthesis of enaminoketones. Tetrahedron Lett. 2004, 45, 6629; (d) Katritzky , A. R. ; Fang , Y. ; Donkor , A. ; Xu , J. Imine acylation via benzotriazole derivatives: The preparation of enaminones. Synthesis 2000, 2029; (e) Fustero , S. ; de la Torre , M. G. ; Jofre , V. ; Carlon , R. P. ; Navarro , A. ; Fuentes , A. S. ; Carrio , J. S. Synthesis and reactivity of new β-enamino acid derivatives: A simple and general approach to β-enamino esters and thioesters. J. Org. Chem. 1998, 63, 8825.
   Google Scholar
• (a) Hickmott , P. W. ; Sheppard , G. Enamine chemistry, XIV: Reaction of α,β-unsaturated acid chlorides with tertiary enamino ketones and esters . J. Chem. Soc., Perkin Trans. 1 1972 , 1038 ; (b) Yapi , A. D. ; Mustofa , M. ; Valentin , A. ; Chavignon , O. ; Teulade , J. C. ; Mallie , M. ; Chapat , J. P. ; Blache , Y. New potential antimalarial agents: Synthesis and biological activities of original diaza-analogs of phenanthrene . Chem. Pharm. Bull. 2000 , 48 , 1886 ; (c) Brown , R. J. ; Carver , F. W. S. ; Hollingsworth , B. L. The synthesis of oximes . J. Org. Chem. 1967 , 32 , 2624 ; (d) Brandt , C. A. ; da Silva , A. C. M. P. ; Pancote , C. G. ; Brito , C. L. ; da Silveira , M. A. B. Efficient synthetic method for β-enamino esters using ultrasound . Synthesis 2004 , 1557 ; (e) Valduga , C. J. ; Squizani , A. ; Braibante , H. S. ; Braibante , M. E. F. The use of K-10/ultrasound in the selective synthesis of unsymmetrical-enamino ketones . Synthesis 1998 , 1019 ; (f) Štefane , B. ; Polanc , S. A new regio- and chemoselective approach to β-keto amides and β-enamino carboxamides via 1,3,2-dioxaborinanes . Synlett 2004 , 698 ; (g) Gao , Y. H. ; Zhang , Q. H. ; Xu , J. X. A Convenient and effective method for synthesizing β-amino-α, β-unsaturated esters and ketones . Synth. Commun. 2004 , 34 , 909 ; (h) Bartoli , G. ; Bosco , M. ; Locatelli , M. ; Marcantoni , E. ; Melchiorre , P. ; Sambri , L. Zn(ClO4)2·6H2O as a powerful catalyst for the conversion of β-ketoesters into β-enamino esters . Synlett 2004 , 239 ; (i) Khodaei , M. M. ; Khosropour , A. R. ; Kookhazadeh , M. Enamination of β-dicarbonyl compounds catalyzed by CeCl3·7H2O at ambient conditions: Ionic liquid and solvent-free media . Synlett 2004 , 1980 ; (j) Arcadi , A. ; Bianchi , G. ; Di Giuseppe , S. ; Marinelli , F. Gold catalysis in the reactions of 1,3-dicarbonyls with nucleophiles . Green Chem. 2003 , 5 , 64 ; (k) Silva , F. C. ; Souza , M. C. B. V. ; Ferreira , V. F. ; Sabino , S. J. ; Antunes , O. A. C. Natural clays as efficient catalysts for obtaining chiral β-enamino esters . Catal. Commun. 2004 , 5 , 151 ; (l) Khosropour , A. R. ; Khodaei , M. M. ; Kookhazadeh , M. A mild, efficient and environmentally friendly method for the regio- and chemoselective synthesis of enaminones using Bi(TFA)3 as a reusable catalyst in aqueous media . Tetrahedron Lett. 2004 , 45 , 1725 ; (m) Khodaei , M. M. ; Khosropour , A. R. ; Kookhazadeh , M. A novel enamination of β-dicarbonyl compounds catalyzed by Bi(TFA)3 immobilized on molten TBAB . Can. J. Chem. 2005 , 83 , 209 ; (n) Potešil , T. Thin-layer chromatography of enamino ketones . J. Chromatogr. 1984 , 312 , 387 ; (o) Stefani , H. A. ; Costa , I. M. ; Silva , D. O. An easy synthesis of enaminones in water as solvent . Synthesis 2000 , 1526 ; (p) Das , B. ; Venkateswarlu , K. ; Majhi , A. ; Reddy , M. R. ; Reddy , K. N. ; Rao , Y. K. ; Ravikumar , K. ; Sridhar , B. Highly efficient, mild and chemo- and stereoselective synthesis of enaminones and enamino esters using silica supported perchloric acid under solvent-free conditions . J. Mol. Catal. A: Chem. 2006 , 246 , 276 ; (q) Yadav , J. S. ; Kumar , V. N. ; Rao , R. S. ; Priyadarshini , A. D. ; Rao , P. P. ; Reddy , B. V. S. ; Nagaiah , K. Sc(OTf)3 catalyzed highly rapid and efficient synthesis of β-enamino compounds under solvent-free conditions . J. Mol. Catal. A: Chem. 2006 , 256 , 234 ; (r) Zhang , Z. H. ; Yin , L. ; Wang , Y. M. A general and efficient method for the preparation of β-enamino ketones and esters catalyzed by indium tribromide . Adv. Synth. Catal. 2006 , 348 , 184 ; (s) Zhang , Z. H. ; Hu , J. Y. Cobalt(II) chloride–mediated synthesis of β-enamino compounds under solvent-free conditions . J. Braz. Chem. Soc. 2006 , 17 , 1447 ; (t) Vohra , R. K. ; Renaud , J. L. ; Bruneau , C. Tertiary 3-aminopropenones and 3-aminopropenoates: Their preparation, with and without lewis acids, from secondary amines and 1,3-diketo compounds . Synthesis 2007 , 731 , and references therein .
   Google Scholar
• (a) Lehuedu , J. ; Fauconneau , B. ; Barrier , L. ; Ourakow , M. ; Piriou , A. ; Vierfond , J. M. Synthesis and antioxidant activity of new tetraaryl pyrroles. Eur. J. Med. Chem. 1999, 34, 991; (b) Arrowsmith , J. ; Jennings , S. A. ; Clark , A. S. ; Stevens , M. F. G. Antitumor imidazotetrazines, 41: Conjugation of the antitumor agents mitozolomide and temozolomide to peptides and lexitropsins bearing DNA major and minor groove-binding structural motifs. J. Med. Chem. 2002, 45, 5458; (c) Haubmann , C. ; Hubner , H. ; Gmeiner , P. Piperidinylpyrroles: Design, synthesis and binding properties of novel and selective dopamine D4 receptor ligands. Bioorg. Med. Chem. Lett. 1999, 9, 3143.
   PubMedGoogle Scholar
• (a) Hantzsch , A. Stereochemical arrangement of atoms in molecules containing nitrogen. Ber. Dtsch. Chem. Ges. 1890, 23, 1474; (b) Fabiano , E. ; Golding , B. T. On the mechanism of pyrrole formation in the knorr pyrrole synthesis and by porphobilinogen synthase. J. Chem. Soc., Perkin Trans. 1 1991, 3371; (c) Ferreira , V. F. ; De Souza , M. C. B. V. ; Cunha , A. C. ; Pereira , L. O. R. ; Ferreira , M. L. G. Recent advances in the synthesis of pyrroles. Org. Prep. Proced. Int. 2002, 33, 411; (d) Kleinspehn , G. G. A novel route to certain 2-pyrrolecarboxylic esters and nitriles. J. Am. Chem. Soc. 1955, 77, 1546; (e) Hamby , J. M. ; Hodges , J. C. α-Amino ketones from amino acids as precursors for the knorr pyrrole synthesis. Heterocycles 1993, 35, 843; (f) Alberola , A. ; Ortega , A. G. ; Sadaba , M. L. ; Sanudo , C. Versatility of Weinreb amides in the knorr pyrrole synthesis. Tetrahedron 1999, 55, 6555; (g) Elghamry , I. Synth. Commun. 2002, 32, 897.
   Google Scholar
• (a) Yadav , J. S. ; Reddy , B. V. S. ; Eeshwaraiah , B. ; Gupta , M. K. Bi(OTf)3/[bmim]BF4 as novel and reusable catalytic system for the synthesis of furan, pyrrole, and thiophene derivatives . Tetrahedron Lett. 2004 , 45 , 5873 ; (b) Braun , R. U. ; Zeitler , K. ; Mueller , T. J. J. A novel one-pot pyrrole synthesis via a coupling–isomerization–Stetter/Paal–Knorr sequence . Org. Lett. 2001 , 3 , 3297 ; (c) Curini , M. ; Montanari , F. ; Rosati , O. ; Lioy , E. ; Margarita , R. Layered zirconium phosphate and phosphonate as heterogeneous catalyst in the preparation of pyrroles . Tetrahedron Lett. 2003 , 44 , 3923 ; (d) Banik , B. K. ; Samajdar , S. ; Banik , I. Simple synthesis of substituted pyrroles . J. Org. Chem. 2004 , 69 , 213 ; (e) Balme , G. Heterocycle synthesis: Pyrrole syntheses by multicomponent coupling reactions . Angew. Chem., Int. Ed. 2004 , 43 , 6238 ; (f) Bharadwaj , A. R. ; Scheidt , K. A. Catalytic multicomponent synthesis of highly substituted pyrroles utilizing a one-pot Sila–Stetter/Paal–Knorr strategy . Org. Lett. 2004 , 6 , 2465 ; (g) Ballini , R. ; Barboni , L. ; Bosica , G. ; Petrini , M. 2,5-Dialkylfurans and nitro alkanes as source of 2,3,5-trialkylpyrroles . Synlett 2000 , 391 ; (h) Raghavan , S. ; Anuradha , K. Solid-phase synthesis of heterocycles from 1,4-diketone synthons . Synlett 2003 , 711 ; (i) Quiclet-Sire , B. ; Quintero , L. ; Sanchez-Jimenez , G. ; Zard , Z. A practical variation on the Paal–Knorr pyrrole synthesis . Synlett 2003 , 75 ; (j) Wang , B. ; Gu , Y. L. ; Luo , C. ; Yang , T. ; Yang , L. M. ; Suo , J. S. Pyrrole synthesis in ionic liquids by Paal–Knorr condensation under mild conditions . Tetrahedron Lett. 2004 , 45 , 3417 ; (k) Wang , B. ; Kang , Y. R. ; Yang , T. ; Yang , L. M. Fe3+-Montmorillonite as effective, recyclable catalyst for Paal–Knorr pyrrole synthesis under mild conditions . Synth. Commun. 2005 , 35 , 1051 .
   Web of Science ®Google Scholar
• (a) Ruault , P. ; Pilard , J. F. ; Touaux , B. ; Boullet , F. T. ; Hamelin , J. Rapid generation of amines by microwave irradiation of ureas dispersed on clay . Synlett 1994 , 935 ; (b) Danks , T. N. Microwave assisted synthesis of pyrroles . Tetrahedron Lett. 1999 , 40 , 3957 ; (c) Minetto , G. ; Raveglia , L. F. ; Sega , A. ; Taddei , M. Microwave-assisted Paal–Knorr reaction—Three-step regiocontrolled synthesis of polysubstituted furans, pyrroles, and thiophenes . Eur. J. Org. Chem. 2005 , 5277 ; (d) Minetto , G. ; Raveglia , L. F. ; Taddei , M. Microwave-assisted Paal–Knorr reaction: A rapid approach to substituted pyrroles and furans . Org. Lett. 2004 , 3 , 389 .
   Google Scholar
• (a) For reports on the application of Ga(OTf)3-promoted reactions in organic synthesis, see (a) Prakash , G. K. S. ; Mathew , T. ; Panja , C. ; Vaghoo , H. ; Venkataraman , K. ; Olah , G. A. Efficient one-pot synthesis of fluorinated benzimidazolines, benzothiazolines, benzoxazolines, and dihydrobenzoxazinones using gallium(III) triflate as a catalyst. Org. Lett. 2007, 9, 179; (b) Deng , X. M. ; Sun , X. L. ; Tang , Y. Highly regioselective rearrangement of 2-substituted vinylepoxides catalyzed by gallium(III) triflate. J. Org. Chem. 2005, 70, 6537; (c) Nguyen , R. V. ; Li , C. J. An annulation toward fused bicyclolactones. J. Am. Chem. Soc. 2005, 127, 17184.
   PubMedGoogle Scholar
• (a) Su , W. K. ; Li , J. J. ; Zheng , Z. G. ; Shen , Y. C. One-pot synthesis of dihydropyrimidiones catalyzed by strontium(II) triflate under solvent-free conditions . Tetrahedron Lett. 2005 , 46 , 6037 ; (b) Su , W. K. ; Hong , Z. ; Shan , W. G. ; Zhang , X. X. A facile synthesis of 1-substituted-1H-1,2,3,4-tetrazoles catalyzed by ytterbium triflate hydrate . Eur. J. Org. Chem. 2006 , 2723 ; (c) Yu , C. M. ; Dai , X. P. ; Su , W. K. Ytterbium(III) triflate catalyzed [3 + 2] cycloaddition of N-aryl imines and epoxides: A novel and solvent-free synthesis of substituted 1,3-oxazolidines . Synlett 2007 , 646 ; (d) Chen , J. X. ; Wu , H. Y. ; Zheng , Z. G. ; Jin , C. ; Zhang , X. X. ; Su , W. K. An approach to the Paal–Knorr pyrroles synthesis catalyzed by Sc(OTf)3 under solvent-free conditions . Tetrahedron Lett. 2006 , 47 , 5383 ; (e) Su , W. K. ; Chen , J. X. ; Wu , H. Y. ; Jin , C. A general and efficient method for the selective synthesis of β-hydroxy sulfides and β-hydroxy sulfoxides catalyzed by gallium(III) triflate . J. Org. Chem. 2007 , 72 , 4524 ; (f) Su , W. K. ; Jin , C. First catalytic and green synthesis of Aryl-(Z)-vinyl chlorides and its plausible addition–elimination mechanism . Org. Lett. 2007 , 9 , 993 ; (g) Su , W. K. ; Jin , C. One-step reaction of Friedel–Crafts acylation and demethylation of aryl-methyl ethers catalyzed by ytterbium(III) triflate . Synth. Commun. 2004 , 34 , 4199 ; (h) Ytterbium triflate–catalyzed Friedel–Crafts reaction: Facile synthesis of diaryl ketones . Synth. Commun. 2004 , 34 , 4249 ; (i) Su , W. K. ; Yang , D. W. ; Li , J. J. Novel process for synthesis of 1,2,4-triazoles: Ytterbium triflate–catalyzed cyclization of hydrazonyl chlorides with nitriles . Synth. Commun. 2005 , 35 , 1435 ; (j) Chen , J. X. ; Wu , H. Y. ; Jin , C. ; Zhang , X. X. ; Xie , Y. Y. ; Su , W. K. Highly regioselective ring opening of epoxides with thiophenols in ionic liquids without the use of any catalyst . Green Chem. 2006 , 8 , 330 ; (k) Chen , J. X. ; Su , W. K. ; Wu , H. Y. ; Liu , M. C. ; Jin , C. Eco-friendly synthesis of 2,3-dihydroquinazolin-4(1H)-ones in ionic liquids or ionic liquid–water without additional catalyst . Green Chem. 2007 , 9 , 972 ; (l) Chen , X. A. ; Zhang , C. F. ; Wu , H. Y. ; Yu , X. C. ; Su , W. K. ; Cheng , J. Solvent-free synthesis of β-hydroxy esters and β-amino esters by indium-mediated reformatsky reaction . Synthesis 2007 , 3233 .
   Web of Science ®Google Scholar
• Zhou , J. C. NMR of enaminones, part 3: 1H, 13C, and 17O NMR spectroscopic studies of acyclic and cyclic N-aryl enaminones: Substituent effects and intramolecular hydrogen bonding . Magn. Reson. Chem. 1997 , 35 , 311 .
   Web of Science ®Google Scholar
• Coromwell , N. H. The reactions of unsaturated ketones and derivatives with amino compounds: Amino ketones . Chem. Rev. 1946 , 38 , 83 .
   PubMedGoogle Scholar
• Šimunek , P. ; Pešková , M. ; Bertolasi , V. ; Machácek , V. ; Lycka , A. Synthesis, NMR, and x-ray characterisation of 6-substituted 4-amino-5-aryldiazenyl-1-arylpyridazinium salts. Tetrahedron 2005, 61, 8130.
   Web of Science ®Google Scholar
• McDougall , R. H. ; Malik , S. H. Reaction of 1,2- and 1,3-dicarbonyl compounds with 1,3-diamines: Some new 1,4-diazepines . J. Chem. Soc. 1969 , 2044 .
   Google Scholar
• Hovey , R. J. ; O'Connell , J. J. ; Martell , A. E. Inner complex chelates, II: Analogs and polar substituted analogs of bis(acetylacetone) ethylenediimine and its metal chelates . J. Am. Chem. Soc. 1959 , 81 , 3189 .
   Web of Science ®Google Scholar
• Bishop , W. S. 2,5-dimethylpyrrole derivatives . J. Am. Chem. Soc. 1945 , 67 , 2261 .
   Google Scholar
• Imuro , K. ; Hanafusa , T. Trifluoroacetylation at the 3-position of 1-(2-aminophenyl)-2,5-dimethylpyrrole in trifluoroacetic acid: Possible remote control of an amino group in electrophilic substitution . Bull. Chem. Soc. Jpn. 1976 , 49 , 1363 .
   Web of Science ®Google Scholar
• Texier-Boullet , F. ; Klein , B. ; Hamelin , J. Pyrrole and pyrazole ring closure in heterogeneous media . Synthesis 1986 , 409 .
   Google Scholar