Intramolecular Oxidative Coupling of Aromatic Compounds. II. The Synthesis of (2RS,3SR)- and (2RS,3RS)-2,3-Dimethyl-1,4-bis(3,4,5-trimethoxyphenyl)butan-1-one and the Determination of Stereochemistry

Abstract

The C- methylation of 3-methyl-1,4-bis(3,4,5-trimethoxyphenyl)butan-1-one (9) gave in a ratio of 4:1 the diastereoisomers, (2RS,3SR)- and (2RS,3RS)-2,3-dimethyl-1,4-bis(3,4,5-trimethoxyphenyl) butan-1-one, (7) and (8) respectively. The stereochemistry of each isomer was determined by conversion into an aryltetralin of known stereochemistry.