Transition metal complexes with sulfur ligands LXXXVII. Coordination of CO to high valent molybdenum sulfur centers: syntheses, properties and structure of stable molybdenum(IV) thiolato carbonyl complexes

Abstract

Thermal thioether- S-desalkylation of the molybdenum( II) carbonyl complexes [Mo(CO) 2(PR 3)(‘ buS 4’)] (R=Ph, Me; ‘ buS 4’ 2−= 1,2-bis(2-mercapto-3,5-di-t-butylphenylthio)ethane(2−)) yields the molybdenum(IV) carbonyl complexes [Mo(CO)(PR 3)(‘ buS 2’) 2] (‘ buS 2’ 2−=3,5-di-t-butyl-1,2-benzenedithiolate(2−)). X-ray structure analysis of [Mo(CO)(PPh 3)(‘ buS 2’) 2] ( 1) shows a pseudo trigonal prismatic coordination of the molybdenum center by a S 4CP donor set. NMR spectra indicate that 1 and [Mo(CO)(PMe 3)(‘ buS 2’) 2] ( 2) possess trans octahedral structures in solution. Thermal desalkylation of [Mo(CO) 3(‘ buS 4’)] at room temperature in high vacuo yields [Mo(CO) 2(‘ buS 2’) 2] ( 4), the first molybdenum(IV) carbonyl complex displaying only biologically relevant thiolate donors in its coordination sphere and being stable at room temperature.