2-Ethynylaziridines as chiral carbon nucleophiles: Stereoselective synthesis of 1,3-amino alcohols with three stereocenters via allenylindium reagents bearing a protected amino group

Allenylindium reagents bearing a protected amino group were effectively pre pared from N-protected 3-alkyl-2-ethynylaziridines by treatment with InI in the presence of Pd(PPh3)(4) and H2O. Stereo-selective addition of the alle nylindium to aliphatic or aromatic aldehydes affords 1,3-amino alcohols bea ring three contiguous chiral centers: while 2,3-trans-2-ethynylaziridines y ield syn,syn-2-ethynyl-1,3-amino alcohols predominantly, 2,3-cis-aziridines give anti,syn isomers selectively. Synthesis of highly substituted ethynyl azetidines is also described.