The preparation from cyclopentadiene trimer of alcohols and ketones containing the perhydro-4,9:5,8-dimethanobenz[f]indene ring system

Abstract

endo,exo,endo-Perhydro-4,9:5,8-dimethanobenz[f]inden-6-exo-ol (2) and other alcohols and ketones containing the perhydro-4,9 : 5,8-dimethanobenz[f]indene ring system in either the endo,exo,endo- or the exo,exo,endo-form have been prepared from cyclopentadiene trimer (1). The acid-catalysed addition of water and various carboxylic acids to the 2,3-double bond of the diene (1) has been investigated. It appears that the degree of Wagner–Meerwein rearrangement accompanying such additions is related to the steric bulk of the addend. The route employed for the preparation of the bridgehead 3a-alcohol (26) involved the stereo- and regio-selective allylic oxidation of the 2,3-olefin (15) with t-butyl perbenzoate and a copper-salt catalyst. The mass and ¹³C n.m.r. spectra of representative alcohols and ketones are reported.