Reactions of 1,3-dielectrophiles with primary amines

At present, the most convenient way for the preparation of 1,3-disubstituted azetidines involves the alkylation of a primary amine with the bis-triflate of a 2-substituted 1,3-propanediol species in the presence of diisopropylethyl-amine 2006JOC7885 . 

Cyclization of a,a-dichloro-/3-mesyloxyimines 171 by means of potassium carbonate in DMSO constitutes a novel approach to a relatively unexplored class of azaheterocycles, that is, 3,3-dichloroazetidines 172 (Equation 43) 1998JOC6 . The use of nucleophilic reagents like potassium cyanide or sodium borohydride in methanol afforded 2-cyano-3,3-dichloroazetidines 173 (Equation 44) and 2-methoxy-3,3-dichloroazetidines 174 (Equation 45), respectively. 

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