72894-66-7Relevant articles and documents
TETRACARBONYLWOLFRAM-KOMPLEXE MIT ZWEI UNTERSCHIEDLICHEN DONORLIGANDEN. I. DARSTELLUNG UND MECHANISMUS DER THERMISCHEN ISOMERISIERUNG
Schenk, Wolfdieter A.
, p. 195 - 204 (2007/10/02)
cis- and trans-tetracarbonyltungsten complexes (R3P)(R'3E)W(CO)4 (R3P, R'3E=i-Pr3P, Ph2-i-PrP, Ph3P, Ph2HP, (Me2N)3P, Ph(i-PrO)2P, (i-PrO)3P, (PhO)3P, Ph3As, Ph3Sb) are obtained from the chlorotetracarbonyltungstates - by several different routes.A cis-trans equilibrium is attained at 20-80 deg C with the trans isomer being thermodynamically more stable in nearly all cases.The cis-trans isomerisation of the phosphine-arsine and phosphine-stibine complexes is shown by ligand exchange experiments to occur via dissociation of the arsine and stibine ligand, respectively.The bis(phosphine) complexes, however, isomerise intramolecularly without bond cleavage.