Preparation and Stereochemistry of the Cobalt(III) Complexes with N,N′-Polymethylenedi(salicylideneamine) and Its Related Compounds

Abstract

Abstract Preparation of two series of the cobalt(III) complexes, Na[Co(CN)2(SB)] and [Co(acac)(SB)], was carried out. CN, acac and SB respectively refer to cyanide anion, acetylacetonate anion and the quadridentate Schiff base anion, N,N′-polymethylenedi(salicylideneamine), N,N′-polymethylenedi(α-methylsalicylideneamine) or N,N′-polymethylenedi(2-hydroxy-1-naphthylmethyleneamine). Efforts to obtain Na[Co(CN)2(SB)] only containing the last Schiff base were unsuccessful. It was concluded from their PMR spectra that, for the dicyano complexes, the structure changes from a trans-form to a cis-one via a distorted trans-form, whereas for the acetylacetonato complexes, it changes from a distorted cis-β-form to an undistorted one with an increase in the length of carbon chain in the bridged polymethylene group of the Schiff bases.