- STEREOSELECTIVE SN2' ADDITIONS OF ORGANOCUPRATES TO HOMOCHIRAL ACYLIC VINYLOXIRANES
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Additions of various methylcopper reagents to the homochiral acylic vinyloxiranes A14, A15, B6-B9, and C5, C6 were performed in order to evaluate E/Z and syn/anti preferences.The unsubstituted oxiranes A14 and A15 gave a mixture of SN2 and SN2' substitution products with the four reagents examined, LiMe2Cu, LiMeCuCN, BrMgMe2Cu, and LiMeCuI*BF3.The more highly substituted systems B6-B9 derived from geraniol and C5, C6 derived from nerol yielded only SN2' products.The (Z)-allylic alcohol derivatives B8 and C6 and LiMeCuCN gave the best anti/syn ratios (99:1 and 97:3, respectively).In both cases the newly formed double bond was exclusively E.
- Marshall, James A.,Trometer, Joseph D.,Cleary, Darryl G.
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p. 391 - 402
(2007/10/02)
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