Investigation of the solvent free isomerisation of cis -Mo(CO) 4 L 2 [L = PPh 2 Et, PPh 3, PPh 2 Me, and P( m -tolyl) 3 ] by diffuse reflectance infrared Fourier transform

Abstract

Thermal analysis of cis-Mo(CO)4L2 [L= PPh2Et, PPh3, PPh2Me and P(m-tolyl)3] revealed that they undergo cis to trans isomerisation under solventless conditions. For L = PPh3 and P(m-tolyl)3, the reaction occurred in the solid state. For L = PPh2Et and PPh2Me the reaction occurred in the melt and was followed by trans isomer solidification. The rate of the solid state isomerisation of cis-Mo(CO)4 (PPh3)2 was investigated by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and the results showed that the reaction was first order. A thermomicroscopic investigation of cis-Mo(CO)4[P(m-tolyl)3]2 revealed that the isomerisation was surface-initiated.KEY WORDS: Solventless reactions, Molybdenum, Isomerisation, Thermal analysis Bull. Chem. Soc. Ethiop. 2011, 25(2), 209-220.