Stereoselective cyclopropanation of enones with ethyl dimethylsulfonium acetate bromide in the presence of DBU

Tetrahedron Letters

Volumn 38, Issue 12, 1997, Pages 2133-2136

  Collado, Iván ^a   Domínguez, Carmen ^a   Ezquerra, Jesús ^a   Pedregal, Concepción ^a   Monn, James A ^b  

^a CSIC   (Spain)

^b ELI LILLY AND COMPANY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CYCLOPROPANE DERIVATIVE; KETONE DERIVATIVE;

ARTICLE; CHEMICAL REACTION; DIASTEREOISOMER; DRUG SYNTHESIS; REACTION ANALYSIS; STEREOISOMERISM;

EID: 0031585109     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)00265-7     Document Type: Article

References (17)

1. 1 Tsuji, T.; Nishida, S. in "The Chemistry of Cyclopropyl Group". Rappoport, Z. Ed.; John Wiley & Sons. 1987. part 1, p 307.
2. 2 Helquist, P. in "Comprehensive Organic Synthesis" Pergamon Press: New York, 1991, vol. 4, pp 968.
3. 3 Simmons, H. E.; Cairns, T. L.; Vladuchick, S. A. Hoines, C. M. Org. Reactions, 1973, 20, 1.
4. 4 (a) Corey, E. J.; Chaykovsky, M. J. Am. Chem. Soc. 1965, 87, 1353.
5. (b) For a review see: Salaün, J. Chem. Rev. 1989, 89, 1247.
6. 5 Nájera, C.; Chinchilla, R.; García-Granda, S. Tetrahedron lett. 1993, 34, 5799 and relevant references cited therein.
7. 6 (a) Moss, R. A. Acc. Chem. Res. 1980, 13, 58.
8. (b) Kort, U. Nachr. Chem. Tech. Lab. 1995, 43, 435.
9. 7 (a) In the synthesis of trans-substituted chromium cyclopropylmethoxycarbene complexes: Barluenga, J.; Bernard, P. L.; Cocellón, J. M. Tetrahedron Lett. 1995, 36, 2153.
10. (b) In the cyclopropanation of optically pure α-(p-tolylsulfinyl) diphenylacrylate: Hamdouchi, C. Tetrahedron Lett. 1992, 33, 1701.
11. 8 Payne, G. B., J. Org. Chem. 1967, 32, 3351.
12. 9 Curley, R. W.; DeLuca, H. F., J. Org. Chem. 1984, 49, 1944.
13. 10 With other activated-electron deficient alkenes, such as esters, aldehydes or nitriles, this reaction does not take place.
14. 11 The use of other bases such as triethylamine led to lower diastereoselectivities.
15. 12 (a) Condensation of α-bromocyclohexenone with EDSA in benzene has been reported to produce the exo adduct. Wender, P. A.; Hillemann, C. L.; Szymonifka, M. J. Tetrahedron Lett. 1980, 21, 2205.
16. (b) During the preparation of this manuscript the synthesis of enantiomerically pure ketone 2a has been described using the same cyclopropanation procedure in acetonitrile. Moher, E. D. Tetrahedron lett. 1996, 37, 8637.
17. 4 and evaporated under reduced pressure (due to the low boiling point of 2a, 4d and 5d, the bath temperature should be kept under 25°C). The crude reaction mixture was purified by flash chromatography (using suitable ethyl acetate/hexane mixtures for each case).