An efficient synthesis of enantiomerically pure 3-hydroxy-β-lactams via zinc induced removal of a chiral auxiliary
摘要:
The diastereoselective synthesis of various beta-lactams 6a-d and 7a-d has been achieved using a chiral acid derived from (+)-+-carene. An efficient zinc induced cleavage of the o-halo ether linkage of these beta-lactams to give enantiomerically pure 3-hydroxy-cis-beta-lactams 8a,b and 9a-d is described. (C) 2000 Elsevier Science Ltd. Ail rights reserved.
An Efficient Synthesis of Optically Active trans-(3R,4R)-3-Acetoxy-4-aryl-1-(chrysen-6-yl)azetidin-2-ones Using (+)-Car-3-ene as a Chiral Auxiliary
作者:Aarif L. Shaikh、Orlando Esparza、Bimal K. Banik
DOI:10.1002/hlca.201100225
日期:2011.12
An efficient enantioselective synthesis of 3‐acetoxy trans‐β‐lactams 7a and 7b via [2+2] cycloaddition reactions of imines 4a and 4b, derived from a polycyclic aromatic amine and bicyclic chiral acid obtained from (+)‐car‐3‐ene, is described. The cycloaddition was found to be highly enantioselective, producing only trans‐(3R,4R)‐N‐azetidin‐2‐one in very good yields. This is the first report of the