A novel strategy involving visible-light-induced functionalization of alkenes for the synthesis of substituted aziridines was developed. The readily prepared N-protected 1-aminopyridinium salts were used for the generation of N-centered radicals. This approach allowed the synthesis of aziridines bearing various functional groups with excellent diastereoselectivity under mild conditions. Moreover, this
Studies on the Reaction of Aziridines with Nitriles and Carbonyls: Synthesis of Imidazolines and Oxazolidines
作者:Shikha Gandhi、Alakesh Bisai、B. A. Bhanu Prasad、Vinod K. Singh
DOI:10.1021/jo062564c
日期:2007.3.1
presence of molecular sieves. Among various triflates, Zn(OTf)2 has been found to be the best. The cleavage of the N-Ts bond of the cyclized products has been studied in order to make it more versatile in synthesis. The mechanistic aspect of the reaction has been studied by using chiral aziridines as substrates. These formal [3 + 2] cycloaddition reactions of aziridines with nitriles and carbonyls proceed
Synthesis of Chiral Organocatalysts derived from Aziridines: Application in Asymmetric Aldol Reaction
作者:Shikha Gandhi、Vinod K. Singh
DOI:10.1021/jo8019863
日期:2008.12.5
We report the synthesis of a new series of highly efficient chiral organocatalysts derived via the regio- and stereoselective ring opening of chiral aziridines with azide anions. The catalysts have proved to be very efficient for a direct asymmetric aldolreaction, both with cyclic as well as acyclic ketones in brine with 2 mol % of catalyst loading, and afforded the products in excellent yields (up