Carbonylation reactions 7. Regioselective synthesis of 2-arylpropionic acids by catalytic carbonylation of styrene derivatives in the presence of palladium compounds: the critical role of the counter anion

The regioselectivity of alkoxycarbonylation of 1-arylethanols catalysed by Pd/acid systems is very sensitive to the nature of the counter anion of the acid: chloride anion favours branched products while tetrafluoroborate and sulfonates anions favour linear products, the latter ones enhancing also p roduct yields. Alkoxycarbonylation of styrenes is also sensitive to the nat ure of the counter anion. (C) 1999 Elsevier Science B.V. All rights reserve d.