‡ New address: College of Materials and Chemical Engineering, Pingxiang University, Pingxiang 337055, China 15288404381@163.com
Abstract
An alternative approach with eco-friendliness and high efficiency for the preparation of unsymmetrical diaryl sulfones has been developed. The strategy takes advantage of the reaction of sulfonyl hydrazides with quinone imine ketals catalyzed by DABCO (triethylenediamine) in ethanol. This transformation proceeds via a Lewis base promoted, direct 1,4-conjugate addition/sulfonylation/alcohol elimination reaction sequence. The protocol provides an efficient approach to access an array of diverse unsymmetrical diaryl and heterodiaryl sulfones, aryl alkyl sulfones and aryl vinyl sulfones in good to excellent yields.
Key words
unsymmetrical diaryl sulfones - eco-friendliness - Lewis base - 1,4-conjugate addition - quinone imine ketals