INSTABILITY OF 15-ELECTRON CP(STAR)MOCL(2)L (L=2-ELECTRON DONOR) DERIVATIVES - X-RAY STRUCTURE OF CP(STAR)MOCL(2)(PME(2)PH)(2) AND [CP(STAR)MOCL(2)(PME(2)PH)(2)]ALCL4

The complex Cp*MoCl2(PMe(2)Ph)(2) (Cp* = eta(5)C(5)Me(5)) has been obtained in good yields from Cp*MoCl4, PMe(2)Ph(2), and Na in the appropriate stoichiometric ratio, and it is also obtained by a ligand redistribution process after reduction of Cp*MoCl3-(PMe(2)Ph) with Na. This compound is oxidized by the CH2Cl2 solvent in the presence of AlCl3 to afford the salt [Cp*MoCl2-, (PMe(2)Ph)(2)]AlCl4. Both compounds have been characterized crystallographically and by H-1-NMR spectroscopy. The reasons for the instability of 15-electron Cp*MoCl(2)L complexes are discussed. The H-1-NMR resonance data for Cp*MoCl(2)L(2) (L = PMe(3), PMe(2)Ph) and [Cp*MoCl2(PMe(2)Ph)(2)](+) are also discussed.