Carbonyl halides of the Group VI transition metals. XII. Isolation of halocarbonyls and halocarbonyl anions of molybdenum and tungsten

Abstract

Dibromotetracarbonylmolybdenum, Mo(CO)₄Br₂, and the dihalotetracarbonyltungsten compounds, W(CO)₄X₂ (where X = Cl, Br), have been isolated and characterized. These highly reactive compounds are all diamagnetic. The trihalotetracarbonyl anions [M(CO)₄X₃]- (M = Mo, W) have been isolated as their tetraethylammonium salts from the parent halocarbonyls. These yellow diamagnetic compounds are the first tetracarbonyl derivatives to be prepared from the parent halocarbonyls.