SYNTHESES AND MOLECULAR-STRUCTURES OF MOLYBDENUM COMPLEXES WITH PHOSPHIDO, DIPHOSPHANYL AND DIPHOSPHENE LIGANDS

The reaction of Cp(o)MoCl(2)(PMe(3))(2)(Cp(o) = C(5)EtMe(4)) with LiPH(2,4,6-Bu(3)(t)C(6)H(2)) (1:2) yielded the terminal molybdenum(II) phosphido complex Cp(o)Mo{PH(2,4,6-Bu(3)(t) C6H2)}(PMe(3))(2) (1). Complex 1 crystallized with one molecule of Li(2,4,6-Bu(3)(t)C(6)H(2)) (2), in which there is a rare example of a one-coordinate Li, in the asymmetric unit. In contrast, the reaction of Cp(o)MoCl(2)(PMe(3))(2) with LiPH(2,4,6-Me(3)C(6)H(2)) (1:2) gave the diphosphanyl complex Cp(o)Mo{P(2,4,6-Me(3)C(6)H(2))PH(2,4,6-Me(3)C(6)H(2))}(PMe(3))(2) (3). When Cp'Mo Cl-2(PMe(3))(2) (4) (Cp' = C(5)H(4)Me) was reacted with LiPH(2,4,6-Me(3)C(6)H(2)) (1:1) the diphosphene complex Cp'Mo{P(2,4,6-Me(3)C(6)H(2))P(2,4,6-Me(3)C(6)H(2))}(PMe(3))(2) (5) was obtained. Crystal structure determinations were carried out on 1-3 and 5. The Mo-P(aryl) distances are 2.250 (3) (1), 2.253(2) (3), and 2.512(2) and 2.624(2) Angstrom (5).