Pd-catalysed coupling reactions in supercritical carbon dioxide and under solventless conditions

The homocoupling of iodoarenes catalysed by Pd(OCOCF3)(2)/P(2-furyl)(3) occurs best in scCO(2) and under solventless reaction conditions, and provides an attractive alternative to previously reported procedures. A comparison of the results in these cases suggests interesting preferential solvation effects are occurring in scCO(2). Each of the methods investigated has advantages and disadvantages which need to be carefully considered before the method of choice is determined.