Studies on terpenes. Part II. Elaboration of 9-methyl-6-p-tolyl-7-oxatricyclo[4,3,0,03,9]nonane into (+)-(1R,3S)-3-isopropenyl-1-p-tolylcyclopentane-1-carboxylic acid, a model for sesquiterpene synthesis
Abstract
The non-enolisable ketone 3-methyl-2-oxo-1-p-tolylnorbornan-3α-ylmethyl toluene-p-sulphonate (IX) undergoes fragmentation on treatment with base to the title cyclopentanecarboxylic acid derivative (XI), a model for the synthesis of spiro[4,5]decane sesquiterpenes [(IV)–(VII)].