Synthesis of 8-methylnonane-1,6,7-trien-4-one and related allenes as potentially useful synthetic precursors

Abstract

The allenic ketone 8-methylnonane-1,6,7-trien-4-one and related allenes have been synthesized from simple commercially available materials. Since allenes analogous to 8-methylnonane-1,6,7-trien-4-one have previously been transformed to substituted bicyclo[3.3.0]octanones via corresponding bicyclo[3.2.0]heptanones, it is anticipated that the present allenic ketone may also undergo similar transformations. Substituted bicyclo[3.3.0]octanones are known synthetic precursors of tricyclic sesquiterpenes. Thus, 8-methylnonane-1,6,7-trien-4-one presents itself as a possible precursor for the synthesis of tricyclopentanoid ring system present in sesquiterpenes such as hirsutene and D⁹⁽¹²⁾-capnellene.

KEY WORDS: 8-Methylnonane-1,6,7-trien-4-one, Allenic ketone, Allenes, Ene-allenes

Bull. Chem. Soc. Ethiop. 2012, 26(1), 103-113.

DOI: http://dx.doi.org/10.4314/bcse.v26i1.11