Thio derivatives of b-diketones and their metal chelates. IV. Adducts of nickel(II) chelates of Monothio-β-diketones with aromatic heterocyclicbases

Abstract

Paramagnetic adducts of nickel(II) chelates of monothio-β-diketones have been obtained with pyridine, γ-picoline, 1,l0-phenanthroline, 2-methyl-1,10-phenanthroline, 2,2'-bipyridyl, and 2,2',2"-terpyridyl. Their paramagnetism and visible reflectance spectra are consistent with octahedral nickel(II). The pyridine and γ-picoline adducts probably have a trans octahedral structure, while there are three possible octahedral configurations for the adducts of the phenanthrolines and bipyridyl. The terpyridyl adduct of Ni(NeCS=CHCOOMe)₂ was obtained in two forms but the data obtained from infrared and visible absorption spectral measurements are insufficient to establish which of the several possible structures occur. The characteristic infrared bands of the adducts are given. The visible absorption spectra of the diamagnetic nickel(II) chelates of the monothio-β-diketones indicate that these ligands lie between diethyl dithiophosphate and diethyl dithiocarbamate in the spectrochemical series.