 The R group can be a range of both basic and acidic sensitive functional groups such as esters, THP ethers, and β-lactams.In addition the reaction is not stereospecific, in that both the "cis" and "trans" isoform can be used to obtain the desired product.The reaction mechanism begins with the creation of the tributyl tin radical with either AIBN or triethylborane, not shown in either step-wise mechanism.