
%0 Journal Article
%A Cambie, RC 
%A Franich, RA 
%T Chemistry of the Podocarpaceae. XXIV. Ring-A modifications of Abieta- 8,11,13-trien-18-oic acid
%J Australian Journal of Chemistry
%D 1970/01/01
%V 23
%N 1
%P 93-105
%K 
%R https://doi.org/10.1071/CH9700093
%U https://www.publish.csiro.au/paper/CH9700093 
%X A convenient route from abieta-8,11,13-trien-18-oic acid (10) to abieta5,8,11,13-tetraen-3-one (27) has been developed involving selective epoxidation of the alkene mixture (2) obtained by oxidative decarboxylation of the acid with lead tetraacetate. Treatment of the 3a,4a-epoxide (9) with lithium diethylamide gives a quantitative yield of the allylic alcohol (19). Brief treatment of this allylic alcohol with N-lithioethylenediamine gives the &#945;, &#946;-unsaturated alcohol (25), which on oxidation affords the enone (24). Methylation of the latter compound with methyl iodide and potassium t-butoxide in t-butanol yields abieta-5,8,11,13-tetraen-3-one (27) in 43% overall yield from the alkene mixture (2). Other reactions of the 3&#945;, 4&#945;-epoxide (9) are reported and discussed. 
