2-Aryl-N-tosylazetidines as Formal 1,4-Dipoles for [4 + 2] Cycloaddition Reactions with Nitriles: An Easy Access to the Tetrahydropyrimidine Derivatives
journal contributionposted on 23.12.2004, 00:00 by B. A. Bhanu Prasad, Alakesh Bisai, Vinod K. Singh
A new synthetic route to 2-aryl-N-tosyl azetidines has been developed starting from N-tosylarylaldimines in two steps in an overall yield of 63−70%. A formal [4 + 2] cycloaddition of these 2-aryl-N-tosylazetidines with nitriles in the presence of BF3·OEt2 has been described for the synthesis of substituted tetrahydropyrimidines. It is proposed that the reaction proceeds in Ritter fashion.