Efficient organocatalytic α-sulfenylation of substituted piperazine-2,5-diones
摘要:
Organocatalytic alpha-sulfenylation of substituted piperazine-2,5-diones is reported through the use of cinchona alkaloids as Lewis bases and electrophilic sulfur transfer reagents. 1-Phenylsulfanyl[1,2,4]triazole, a novel Sulfur transfer reagent, gave excellent product yields with a number of substituted piperazine-2,5-diones under mild conditions. Catalyst loading, stoichiometry Of Sulfur electrophile, temperature, and solvent were optimized to achieve high product yields. (C) 2009 Elsevier Ltd. All rights reserved.