The chemistry of terpenes. Part 24. Some oxidation products of 1,5,5,6-tetramethylcyclohexa-1,3-diene (α-pyronene)

Abstract

r-3,6-Epidioxy-3,t-4,5,5-tetramethylcyclohexene (2), formed by dye-sensitised photo-oxygenation of α-pyronene(1) is reduced by triphenylphosphine to r-3,4-epoxy-4,t-5,6,6-tetramethylcyclohexene (7) and by lithium aluminium hydride to 1,5,5,t-6-tetramethylcyclohex-2-ene-r-1,c-4-diol (11). r-3,4-Epoxy-1,5,5,t-6-tetramethylcyclohexene (6) is the major product of the reaction in ether of perbenzoic acid with α-pyronene (1). From these oxidation products a number of diols and ketols have been obtained.