Nitrido-bis triphenylphosphorus l Pentacarbonyl Acetato Group 6 Metal

p-NITRIDO-BIS(TRIPHENYLPHOSPHORUS)(l +) PENTACARBONYL ACETATO GROUP 6 METAL 

All operations are carried out under nitrogen, with rigorous exclusion of air and moisture. Solvents are dried and deoxygenated by distillation from sodium benzophenone solution and collected under an Nj atmosphere. 

The IR absorption bands for the three pentacarbonyl acetato compounds can be seen in Table II. Four bands are found in the CO stretching region, and two bands are attributed to the acetate moiety. The proton and C NMR resonance peaks are listed in Table III for this family of compounds. 

In general, the acetato complexes of the Group 6 metals are stable in the solid state, but they must be stored in a freezer for prolonged periods. Their solutions are very air sensitive, and after several days the M(CO)e complex is formed even under a Nj atmosphere. The Group 6 acetato complexes are soluble in organic ethers [tetrahydrofuran (THF), diethyl ether, etc.], acetonitrile, dichloromethane, and in other polar solvents such as methanol and ethanol. These complexes are insoluble in hydrocarbon solvents, for example, hexane or benzene. 

Group 6 pentacarbonyl acetato complexes have been also found to undergo addition of alkyl halides (Mel) to produce alkyl acetates and the pentacarbonyl halide metal complex. When allyl halides are used instead of alkyl halides, an oxidative addition product is formed, which contains the allyl, halide, and acetate ligands bonded to the metal. 

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