Regio- and enantio-selective photodimerisation of cyclohex-2-enone as an inclusion complex with a new optically active host, (–)-1,4-bis[3-(o-chlorophenyl)-3-hydroxy-3-phenylprop-1-ynyl]benzene: preparation of the optically pure (–)-syn-trans-dimer of cyclohex-2-enone

Abstract

Photoirradiation of a 1 : 2 inclusion compound of (–)-1,4-bis[3-(o-chlorophenyl)-3-hydroxy-3-phenylprop-1-ynyl]benzene and cyclohex-2-enone as an aqueous suspension gave the (–)-syn-trans-dimer of cyclohex-2-enone in 48% ee, which on an optical resolution by complexation with (–)-1,6-bis(o-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol afforded the optically pure enantiomer.