An alternative synthesis of chlorinated biphenyl methylsulfonyl metabolites

Published methods of synthesizing chlorinated biphenyl methylsulfonys require the separation of a complex mixture of impurities and isomers using both normal and reverse phase HPLC. Even with semi-preparative scale equipment, the process is tedious and time-consuming. In this report, the palladium-catalyzed addition of an aryl iodide to an aryl trimethylstannane has been exploited to produce these compounds in high purity (≥99%) using conventional techniques of purification. The reaction has been demonstrated for a group of methylsulfonyl CBs representing 0 to 3 -chlorine interactions between the biphenyl rings and with the methylsulfonyl group at either the 3- or 4-position.