Stereoselective chelate and amino-acid synthesis with chelated 2-iminopropionate; X-ray crystal and molecular structures of α-(N2-2-aminoethylamidino)alaninato-ONN″N‴-(ethylenediamine)cobalt(III) and α-(N2-2-aminoethylamidino)alanine-NN″N‴-(chloro)ethylenediaminecobalt(III) tetrachlorozincates

Abstract

An intramolecular reaction follows the rapid addition of CN^– at the imine centre of the bis(ethylenediamine)-2-iminopropionatocobalt(III) ion (1) where a deprotonated amine centre attacks the added CN group to give a quadridentate amidine with substantial stereospecificity; the crystal and molecular structures of the tetrachlorozincates of two inter-related complexes, α-(N²-2-aminoethylamidino)alaninato-ONN″N‴-(ethylenediamine)cobalt (4) and α-(N²-2-aminoethylamidino)alanine-NN″N‴-(chloro)ethylenediaminecobalt (6), have been determined.