PAPER	Synthesis 2004: 2479-2484   DOI: 10.1055/s-2004-831203
© Georg Thieme Verlag Stuttgart · New York
One-Pot Stereoselective Synthesis of anti 3-Alkyl and 3-Aryl-N-p-tosyl-aziridine-2-ketones and 3-Aryl-N-p-tosyl-aziridine-2-carboxylates
Dianjun Chen, Cody Timmons, Li Guo, Xin Xu, Guigen Li*
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061, USA e-Mail: guigen.li@ttu.edu;
Received 22 April 2004

Abstract

An efficient and practical synthesis of N-p-tosyl-aziridine-2-ketones and carboxylates through the use of α,β-unsaturated esters and ketones has been reported. The synthesis was conducted via a one-pot procedure consisting of aminohalogenation and in situ intramolecular S_N2 substitution. Triethylamine was found to be an effective base for the in situ cyclization for most substrates. Interestingly, for several enone cases, a slightly modified procedure in which 1.0 equivalent of p-TsNCl₂ was slowly added into 2.0 equivalents of enone for aminohalogenation followed by quenching with aqueous Na₂SO₃ resulted in crude aziridines which were proven to be nearly pure by the crude ¹H NMR analysis. Moderate to good yields and excellent anti stereoselectivity were achieved for 21 examples.

Key words

aziridination - aminohalogenation - haloamines - cinnamates - enones