A practical method for the aziridination of α,β-unsaturated carbonyl compounds with a simple carbamate utilizing sodium hypochlorite pentahydrate

The efficient formation of tert-butyl N-chloro-N-sodio-carbamate by the reaction of simple tert-butyl carbamate with sodium hypochlorite pentahydrate (NaOCl·5H₂O) would be a practical and green method for the aziridination of α,β-unsaturated carbonyl compounds. The process described herein is transition-metal free, all of the materials are commercially available, the byproducts (NaCl and H₂O) are environmentally benign and the reaction is stereoselective. The resulting aziridines are potential precursors of amino acids.

Aryl iodide mediated aziridination of alkenes

[reaction: see text] Aryl iodide mediated aziridination of a variety of alkenes with N-aminophthalimide under mild conditions (m-CPBA, K2CO3, CH2Cl2, 25 degrees C) was achieved in moderate to good yields (up to 94%). By recovering the aryl iodide, a recyclable system is developed with product yield over 79% attained for the aziridination of trans-1,2-diphenylethylene.

The stereoselective synthesis of aziridine analogues of diaminopimelic acid (DAP) and their interaction with dap epimerase

Aziridine analogues of diaminopimelic acid (DAP) have been prepared stereoselectively for the first time and evaluated as inhibitors of DAP epimerase. (2R,3S,3'S)-3-(3'-Aminopropane)aziridine-2,3'-dicarboxylate was synthesised and shown to be a reversible inhibitor of DAP epimerase with an IC(50) value of 2.88 mM. (2S,4S)- and (2S,4R)-2-(4-Amino-4-carboxybutyl)aziridine-2-carboxylic acid (ll-azi-DAP and dl-azi-DAP ) were made as pure diastereomers, and both were shown to be irreversible inhibitors of DAP epimerase. ll-Azi-DAP selectively binds to Cys-73 of the enzyme active site whereas dl-azi-DAP binds to Cys-217 via attack of sulfhydryl on the methylene of the inhibitor aziridine ring. These observations are consistent with the two base mechanism proposed for the epimerization of ll-DAP and meso-DAP by DAP epimerase.

Enantioselective aziridination of alkenes with N-aminophthalimide in the presence of lead tetraacetate-mediated chiral ligand

[reaction: see text] Reaction of various N-enoyl oxazolidinones 5a-f with N-aminophthalimide and lead tetraacetate in the presence of camphor-derived chiral ligands provides the desired N-phthalimidoaziridines 6a-f in good to high enantiomeric excess (67-95% ee) at 0 degrees C within 15 min. The absolute stereochemistry of the corresponding aziridine derivatives was established by chemical correlations.

A facile and highly diastereoselective aziridination of chiral camphor n-enoylpyrazolidinones with n-aminophthalimide

Reaction of various chiral camphor N-enoylpyrazolidinones 2a-g with N-aminophthalimide in the presence of lead tetraacetate in CH(2)Cl(2) proceed smoothly afford the corresponding N-phthalimidoaziridines (3a-e, 4f-g) with excellent material yields (86-95%) at room temperature in 5 min. High levels of diastereoselectivities (up to >95:5 dr) were obtained. The solvent effect was investigated, and the auxiliary can be easily recovered in high yields under mild reaction conditions.