Optical Resolution and Enantioselective Rearrangements of Amino Group Containing Oxiranyl Ethers

Resolution protocols for 2-benzyloxymethyl-3-diethylaminomethyloxirane and 2-benzyloxymethyl-3-piperidinomethyloxirane have been developed. In the presence of organometallic bases enantioselective rearrangement of the newly separated oxirane enantiomers provides chiral oxetanes or cis-but-2-ene-1,4-diol derivatives without any racemization. The stereochemistry of the oxetanes was investigated by H-1 NMR and molecular modeling. A novel method using an atropisomeric dicarboxylic acid as a chiral solvating agent in H-1 NMR for the determination of the enantiomeric excess of the products is also reported. (C) 2002 Elsevier Science Ltd. All rights reserved.