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Efficient Organocatalytic alpha-Sulfenylation of Substituted Piperazine-2,5-diones.

ABSTRACT: 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.

SUBMITTER: Dubey R

PROVIDER: S-EPMC2699310 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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Efficient Organocatalytic alpha-Sulfenylation of Substituted Piperazine-2,5-diones.

Dubey Ramin R Polaske Nathan W NW Nichol Gary S GS Olenyuk Bogdan B

Tetrahedron letters 20090701 30

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. ...[more]

PMID: 20161311

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