PREPARATION AND CHARACTERIZATION OF [(LL)CL2MO](2)(MU-SPR)(2) COMPOUNDS WITH PR=N-PROPYL AND LL=PRSCH2CH2SPR AND ET(2)PCH(2)CH(2)PET(2) - FURTHER EXAMPLES OF C-S BOND-CLEAVAGE AND OXIDATIVE ADDITION ACROSS AN MO-MO QUADRUPLE BOND

Two dimolybdenum(III) complexes with edge-sharing bioctahedral geometr ies have been synthesized and structurally characterized by three-dime nsional, single-crystal X-ray diffractometry. Both [(PrSCH2CH2SPI)Cl2M o](2)(mu-SPr)(2).0.5CH(2)Cl(2) and [(Et(2)PCH(2)CH(2)PEt(2))Cl2Mo](2)( mu-SPr)(2) where Pr is n-propyl and Et is ethyl (hereafter referred to as 1 and 2, respectively) crystallize in the monoclinic system with t wo formula units per cell (C2/m and P2(1)/ c, respectively). The Mo-Mo bond distances of 2.682(6) Angstrom for 1 and 2.769(1) Angstrom for 2 are characteristic of Mo-Mo double bonds. Bond lengths and angles are internally consistent and the van der Waals interactions are normal. Utilizing cone angle calculations, a 'ligand profile' describes the st eric bulk about the phosphorus atoms in 2 looking down the Mo-P bonds. The resulting maximum half cone angles, phi/2, are 62+/-1.0 degrees. Compound 1 was prepared by a reaction involving carbon-sulfur bond cle avage, and separately, by a reaction involving oxidative addition of P rSSPr across the Mo-Mo quadruple bond in Mo2Cl4(PrSCH2CH2SPr)(2). Comp ound 2 was prepared from compound 1 by ligand substitution.