Halogen–lithium exchange versus deprotonation: regioselective mono- and dilithiation of aryl benzyl sulfides. A simple approach to α,2-dilithiotoluene equivalents
reactions between aryl benzyl sulfides and alkyllithiums were investigated. The resultant mono- and dilithiated intermediates were converted into the corresponding aldehydes and boronic, or carboxylic acids in good yields. It was found that diethyl ether stabilizes the ortho-lithiated compounds toward isomerisation to the benzylic derivatives. The process occurs easily in THF at low temperature and is
An operationally simple EosinYcatalyzed sulfenylation of hydrazones has been realized to afford a range of thioethers under visible light. The methodology provides high yields of thioethers under ambient conditions employing readily available and inexpensive starting materials. The reaction has broad substrate scope and is compatible with various functional groups.
A facile and sustainable protocol for the thiolation of hydrazones with sodiumsulfinates has been developed in the presence of CuBr2 and DBU in DMF to afford diverse benzylic thioethers. Control experiments reveal a radical pathway involving a thiyl radical as a key intermediate.
sulfonohydrazides has been designed for the efficient construction of benzylic thioethers in excellent yield under mild reaction conditions. The current approach avoids the widely used thiolation reagent, thiols. The commercial availability of the base and reagents, broad substrate scope, and convenient reaction procedure make it an attractive method for benzylic thioether synthesis.