Reaction of Aryl Dehydroabietates and Aryl Homodehydroabietates with Titanium (IV) Chloride

Study on chemical transformation of dehydro abietic acid Part 4

Abstract

Examination was made of the reactions of aryl dehydroabietates and aryl homodehydroabietates with titanium (IV) chloride by varying the aryl group to phenyl, m-tolyl or the 2, 6-xylyl groups. The reaction proceeded in one of the three pathways (Fries rearrangement, decarboxylation and hydrolysis) depending on the structure of the aryl group and acid component.
Decarboxylation occurred in the case of phenyl and m-tolyl dehydroabietates, to give dehydroabietane. Fries rearrangement occurred in the case of 2, 4-xylyl and m-tolyl homodehydroabietates, and hydrolysis was observed for phenyl and 2, 6-xylyl homodehydroabietates.