Reaction of organocupurates with 2-pyridyl thiol esters or with 2-pyridyl esters

Abstract

Reaction of lithium dialkylcuprates with 2-pyridyl thiol esters or with 2-pyridyl esters affords the corresponding ketones in high yields under mild conditions. Carboxylic esters are exclusively formed from the reaction of lithium dialkylcuprates with 2-pyridyl thiol esters or 2-pyridyl esters in the presence of oxygen. This observation is in marked contrast with earlier finding that oxidation of lithium dialkylcuprates with oxygen gives symmetric coupling products. Reaction of mixed cuprates with 2-pyridyl thiol esters or with 2-pyridyl esters is also investigated in order to establish the scope and limitations of this useful method.