GENERAL SYNTHESES OF (RPPH(2))MO(CO)(5) AND (RDBP)MO(CO)(5) COMPLEXESFROM PH(2)PLI AND DBPLI VIA SINGLE-ELECTRON TRANSFER CATALYSIS

Lithium diphenylphosphide and lithium dibenzophospholide (LiDBP) react rapidly at ambient temperature in dry tetrahydrofuran solutions with Mo(CO)(6) to form [(LiPPh(2))Mo(CO)(5)] and [(LiDBP)Mo(CO)(5)], respec tively. These two compounds may be alkylated with halocarbons (RX) or protonated with acetic acid in the same reaction vessel to give good y ields of (RPPh(2))Mo(CO)(5), (HPPh(2))Mo(CO)(5), (RDBP)Mo(CO)(5) or (H DBP)Mo(CO)(5). These compounds have been characterized by elemental an alyses, physical properties, H-1, C-13{H-1}, (31)p{H-1} and Mo-95 NMR spectroscopy and infrared spectroscopy. Three hydrogen shift isomers a re formed in the reaction of [(LiPPh(2))Mo(CO)(5)] with ClCH2C=CH, viz , (HC=CCH(2)PPh(2))Mo(CO)(5), (H2C=C=CHPPh(2))Mo(CO)(5) and (CH3C=CPPh (2))Mo(CO)(5). The crystal structures of the two latter compounds and (1-trans-2-buteneyldibenzophosphole)moly pentacarbonyl, (crotyl DBP)Mo (CO)(5), (at 173K) have been determined. These compounds crystallize i n the monoclinic P2(1)/n, triclinic <P(1)over bar>, and triclinic <P(1 )over bar> space groups respectively, in unit cells with the following dimension: a = 16.355(3)Angstrom, b = 8.114(1)Angstrom, c = 16.617(3) Angstrom, beta = 113.09 degrees, V = 2028.5(6)Angstrom(3), rho(calc) = 1.507 g cm(-3), Z = 4; a = 8.253(1)Angstrom, b = 10.497(2)Angstrom, c = 11.933(2)Angstrom, alpha= 89.89(1)degrees, beta = 83.61(1)degrees, gamma 77.03(1)degrees, V = 1000.8(4)Angstrom(3), rho(calc) = 1.527 g c m(-3), Z = 2 and a = 7.894(2)Angstrom, b = 10.137(2)Angstrom, c = 13.9 59(2)Angstrom, alpha = 76.17(1)degrees, beta = 81.42 degrees(1)degrees , gamma = 68.17(1)degrees, V = 1004.6(4)Angstrom(3), rho(calc) = 1.568 g cm(-3), Z = 2, respectively. Least-squares refinements converged to R(F) = 0.0494, 0.0425, and 0.0406 for 2655, 3333 and 2612 independent (I > 2 sigma(I), F > 4 sigma(F), and I > 2 rho(I)) reflections, respe ctively. Spectroscopic data indicate that the RDBP ligands are better pi-acceptors than the RPPh(2) ligands, but show little differentiation among any of the alkyl substituents.