References
- 1977-78 . Syntex Postdoctoral Fellow
- Posner , G. H. 1972 . Org. React. , 19 : 1
- House , H. O. and Umen , M. J. 1973 . J. Org. Chem. , 38 : 3893
- Posner , G. H. and Brunelle , D. J. 1973 . Chem. Comm. , : 907
- Grieco , P. A. , Pogonowski , C. S. and Burke , S. 1975 . J. Org. Chem. , 40 : 542
- Boeckman , R. K. , Bershas , J. P. , Clardy , J. and Solheim , B. 1977 . J. Org. Chem. , 42 : 3630
- Katzenellenbogen , J. A. 1976 . Science , 194 : 139 For reviews of the various syntheses of this compound C. A. Henrick, Tetrahedron, 33, 1845(1977)
- Clark , R. D. and Untch , K. G. J. Org. Chem. , The cyclobutenyl esters 2–5 were prepared by TiCl4 catalyzed cycloaddition of ethyl or methyl propiolate to the requisite silyl enol ether, submitted for publication
- Cycloaddition of ethyl crotonate to t-butyl-dimethylsilyloxy cyclopentene gave a separable mixture of 8 and 19 (reference 6). NMR data for 8, δ 0.86 (s, 9H), 1.12 (d, 3H, J = 6 Hz), 2.00 (m, 2H, H-5,6), 2.74 (d, 1H, J = 8 Hz), 3.64 (s, 3H); 19, δ 0.88 (d, 3H, J = 5 Hz), 2.42 (m, 1H, H-5), 2.45 (d, 1H, J = 9 Hz, H-7), 3.50 (m, 1H, H-6), 3.62 (s, 3H)
- Campbell , A. and Rydon , R. N. 1953 . J. Chem. Soc. , 300 : 6 W. G. Dauben and J. R. Wiseman, J. Amer. Chem. Soc., 89, 3545(1967)
- Cyclobutenecarboxylic acid was treated with ethereal diazomethane and after drying (sodium sulfate) the solution was added to the organometallic reagent thus avoiding isolation of the somewhat unstable ester 1
- House , H. O. , Latham , R. A. and Slater , C. D. 1966 . J. Org. Chem. , 31 : 2667
- Direct methylation of the species generated in the conjugate addition reaction proved to be sluggish even in the presence of 25% HMPA. This is presumably due to the high degree of aggregation of the magnesium enolate and could possibly be overcome if lithium diisopropenyl cuprate were used instead of the copper catalyzed Grignard
- Lactone 20 is produced in 38% yield during formation of the acid chloride. Use of the sodium salt of the acid should prevent formation of this material
- Zurflüh , R. , Dunham , L. L. , Spain , V. L. and Siddall , J. B. 1970 . J. Amer. Chem. Soc. , 92 : 425
- Brannock , K. C. , Bell , A. , Burpitt , R. D. and Kelly , C. A. 1964 . J. Org. Chem. , 29 : 801 B. B. Snider, J. Org. Chem., 41, 3061(1976)