A Geomimetic Approach to the Formation and Identification of Fossil Sterane Biomarkers in Crude Oil: 18‐nor‐D‐homo‐Androstane and 5α, 14β‐Androstane. Issue 35 (1st July 2015)

• Record Type: Journal Article
• Authors: Bender, Matthias; Schmidtmann, Marc; Summons, Roger E.; Rullkötter, Jürgen; Christoffers, Jens
• Is Part Of: Chemistry. Volume 21:Issue 35(2015)
• Page Start: 12501
• Page End: 12508
• Publication Date: 2015-07-01
• Subjects: crude oil -- fossil biomarkers -- natural products -- steroids -- structure elucidation; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201502148
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: A diazonium ion derived from 18‐aminoandrostane rearranged upon decomposition by a carbonium and a carbenium ion to furnish a mixture of a cyclopropanated compound and twoD ‐ homo ‐androstenes. Hydrogenation of this mixture gave the saturated hydrocarbons, 18‐ nor ‐D ‐ homo ‐androstane and 5α, 14β‐androstane, which are both fossil sterane biomarkers in Neoproterozoic crude oil. The so far unknown constitution and configuration as well as the geochemical genesis were established by this experiment. The starting material for this investigation, 18‐aminoandrostane, was prepared in twelve steps from androstan‐17‐one (12.5 % overall yield) with a Barton reaction as the key step. Abstract : New old fossils : Androstane biomarkers were identified by geomimetic rearrangement reactions of the androstane skeleton (see scheme).