Efficient Organocatalytic alpha-Sulfenylation of Substituted Piperazine-2,5-diones.
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.
Dubey
Ramin
R
Department of Chemistry, The University of Arizona, Tucson, AZ 85721.
Polaske
Nathan W
NW
Nichol
Gary S
GS
Olenyuk
Bogdan
B