title: Enantioselective organocatalytic alpha-sulfenylation of substituted diketopiperazines.
abstract: The asymmetric organocatalytic alpha-sulfenylation of substituted piperazine-2,5-diones is reported, with cinchona alkaloids as chiral Lewis bases and electrophilic sulfur transfer reagents. Catalyst loadings, the type of sulfur transfer reagent, temperature and solvent were investigated in order to optimize the reaction conditions. The effects of ring substitution and the type of catalyst on the yield and enantioselectivity of the reaction are reported.
authors.affiliation: Department of Chemistry and Biochemistry, The University of Arizona, 1306 E University Blvd, Tucson, AZ 85721, USA.
authors.forename: Nathan W
authors.initials: NW
authors.lastname: Polaske
authors.forename: Ramin
authors.initials: R
authors.lastname: Dubey
authors.forename: Gary S
authors.initials: GS
authors.lastname: Nichol
authors.forename: Bogdan
authors.initials: B
authors.lastname: Olenyuk