An efficient approach to chiral cis-3,4-epoxy alcohols
摘要:
A new method for the synthesis of cis-3,4-epoxy alcohols has been developed by employing hydroboration of chiral cis-vinylepoxides or syn-chlorohydrins. (C) 1998 Elsevier Science Ltd. All rights reserved.
Diastereoselective Chloroallylboration of α-Chiral Aldehydes
摘要:
Double asymmetric reaction of chiral (Z)-(gamma-chloroallyl)borane, 2, with alpha-chiral aldehydes (3-7) provide a new practical method for the generation of 2,3-syn-3,4-anti and 2,3-syn-3,4-syn chiral vinylchlorohydrins (8-17) and vinyl epoxides(18-27). Both enantiomers of 2 exhibited excellent diatereoselectivity (greater than or equal to 90 de) for matched cases. The mismatched cases yielded moderate to good diastereoselectivity.