IDENTIFICATION OF LONG-CHAIN ISOPRENOID ALKYLBENZENES IN SEDIMENTS AND CRUDE OILS

Abstract

A series of novel methylated phytanylbenzenes (phytanylbenzene, 1-methyl-3-phytanylbenzene, 1,4-dimethyl-2-phytanylbenzene, 1,2-dimethyl-4-phytanylbenzene and 1,2,4-trimethyl-5-phytanylbenzene) have been identified in sediment extracts and oils ranging in age from Miocene to Permian. Identifications were based on comparison of mass spectra and Chromatographie data of synthetic methylated phytanylbenzenes with those of geologically occurring methylated phytanylbenzenes and by coinjections with the standards. Although methylated phytanylbenzenes are structurally related to the methylated 2-methyl-2-(4,8,12-trimethyltridecyl)chromans, components also present in the samples studied, the former do not appear to be the diagenetic derivatives of the latter. The methylated phytanylbenzenes are thought to be derived diagenetically from isoprenoid quinones or may represent a direct biosynthetic origin from specific archaebacteria.