Technetium-phospine complexes. Diethylphenylphosphonite complexes of technetium(III) and mixed ligand complexes of technetium(I) with carbonyls and diethylphenylphosphonite, and crystal and molecular structure of cis-dicarbonyltetrakis(diethylphenylphosphonite)technetium(I) perchlorate

Abstract By reaction of trans-[TxC 2 (P(OEt) 2 Ph) 4 ]ClO 4 (X = Cl, Br, I) with carbon monoxide at room pressure, the cis- and trans-[Tc(CO) 2 (P(OEt) 2 Ph) 4 ]ClO 4 isomers were obtained. To this purpose the complexes trans-(TcX 2 (P(OEt) 2 Ph) 4 ]Y (X = Br, I and Y = ClO 4 - , 1 - ) were therefore synthesized. The formulation of all complexes is substantiated by elemental analysis, magnetic and conductivity measurements, i.r. and 1 H n.m.r. spectra and for the cis-isomer also by X-ray analysis. In the latter complex the technetium atom presents an octahedral coordination with some degree of distortion. The four TcP distances are 2.38(1), 2.41(1), 2.44(1), 2.44(1) A , and the two TcCO distances are both 1.90(2) A .