Synthesis, spectroscopy, bonding and structure in phosphido bridged bimetallics derived from bent metallocenes of molybdenum and tungsten and from group 6 metal carbonyls

Synthesis of monophosphido-bridged compounds and phosphido-hydrido-dibridged complexes involves the reaction of group six metal carbonyls with electron rich terminal phosphido metallocenes. Spectroscopic and EHMO calculations reveal that electron acceptability of M'(CO)4 units in dibridged complexes is higher than that of M'(CO)5 units in monobridged complexes. X-ray analysis enables the determination of W-W distance in a tungsten complex, which suggests a metal-metal interaction.