Synthesis and structure of novel arene chromium complexes with normal thiophosphorous esters as ligands

Reaction of ArCr(CO)(3) with normal thiophosphorous esters P(SR)(3) under c onditions of "indirect" photochemical substitution gave a series of novel c hromium complexes ArCr(CO)(2)P(SR)(3), whose structure was proved by NMR an d IR spectroscopy. X-ray diffraction was used to find that the phosphorothi oite ligand in dicarbonyl(mesitylene)(triphenyl phosphorotrithioite)chromiu m in crystal has a conformation with the phenylthio groups cis, gauche, and trans to the Cr-P bond. This conformation is radically different from thos e characteristic of "free" phosphorothioites.