Planar chiral C6-substituted oxa7orthocyclophenes were designed and synthesized, and their stereochemical behavior was analyzed. The Kumada–Tamao coupling of the C6-iodo-substituted oxacyclophene enabled the efficient and divergent synthesis of C6-substituted derivatives. The stereochemical analysis of the oxacyclophenes revealed that the iodo- and methyl-substituted derivatives have reasonable stereochemical stability. The planar chirality of the methyl-substituted oxacyclophene was successfully transformed into central chirality by epoxidation without loss of enantiomeric purity.
Hashimoto et al. (Wed,) studied this question.