Tin-Free Radical Carbonylation:Thiol Ester Synthesis Using AlkyI Allyl Sulfone Precursors,Phenyl Benzenethiosulfonate,and CO

摘要

Free-radical carbonylation is synthetically very useful in preparing various carbonyl compounds.Synthetic methods based on free-radical carbonylation utilize mainly highly toxic organotin reagents as mediators.In our efforts to address the problems associated with toxic organotin reagents,we reported that the use of alkyl allyl sulfone precursors is one of the most useful and reliable methods for the generation of alkyl radicals under tin-free conditions and are very effective in radical carbon-carbon bond-formation reactions.In our continued efforts to achieve tin-free radical carbon-carbon bond formations,we have recently focused on tin-free radical carbonylations that use alkyl allyl sulfone precursors to prepare thiol esters [Eq.(1)].