GEOSYNTHESIS OF ORGANIC-COMPOUNDS .2. METHYLATION OF PHENANTHRENE ANDALKYLPHENANTHRENES

A crude oil and several shales which contain anomalously high concentr ations of phenanthrene, 1-methylphenanthrene, 1,7-dimethylphenathrene, and retene have been shown to contain relatively high concentrations of their corresponding 9-methyl counterparts. In laboratory experiment s carried out under mild conditions, each of the phenanthrenes has bee n shown to be substituted preferentially at the 9-position when a meth yl donor was heated with the substrate in the presence of a clay catal yst. These observations have been interpreted as evidence for a sedime ntary methylation process.