Scientists discovered a simpler way to synthesize Aziridines

Dr. Mahesh Paudyal, co-author of the science paper
Chemists at University of Texas-Southwestern Medical Center have discovered a simpler route to synthesize aziridine, a three-membered nitrogen analogs of epoxide rings. Aziridines are present in a number of biologically active natural products and are very important synthetic building blocks because they are extensively used to introduce nitrogen atom into complex molecules, including medicinal drugs. The current aziridination methods always need a protecting group on the nitrogen atom. The protecting group groups provide stability to the molecule but the removal of such protecting group needs harsh conditions, and hence is problematic.

Jat et al. have developed a direct and simple one-step method for preparing N–H and N–Me aziridines from alkenes under mild conditions that avoids the need for an N-protecting group (Science,2014, 343, 61). This aziridination method involves the reaction of an alkene with the aminating agents DPH (dinitrophenyl-hydroxylamine) or N–Me–DPH in the presence of a rhodium catalyst, which produces N–H or N–Me aziridines at ambient temperature.

The simple route to aziridines can will help medicinal and natural products chemists © Science/AAAS

“The major challenge now is to develop an asymmetric version of this reaction that will selectively provide a single mirror-image form (enantiomer). This is extremely important in synthesizing drug molecules because two enantiomers of a molecule show different biological activities,” says Mahesh Paudyal, a co-author of the paper at the University of Texas Southwestern Medical Center.

[For detailed understanding and coverage: Please see “This week in Science (page 5) and Perspective (page 34)” of the same issue of Science, Chemistry World – January 9, 2014 (online), C&EN News- January 6, 2014 (online)]

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