Complexes derived from the reactions of diphenylphosphinoacetic acid. Part 3. Dimetal complexes from [Mo2Cl8](4-) and [Re2Cl8](2-)

摘要

Diphenylphosphinoacetic acid (1) reacts with K4MoCl8 in refluxing methanol to afford the centrosymmetric dimolybdenum(II) complex Mo2Cl4(mu-Ph2PCH2CO2Me)(2) (2) that contains two trans P,O bridging phosphine-ester ligands, an eclipsed rotational geometry, and a Mo-Mo quadruple bond distance of 2.1450(8) Angstrom. The corresponding reactions of 1 with (n-Bu4N)(2)Re2Cl8 in refluxing methanol and ethanol yield the paramagnetic, dirhenium(111,11) complexes Re2Cl5(Ph2PCH2CO2R)(3) (R = Me (3) or Et (4)) in which the phosphine-ester ligands are P-bound. A crystal structure determination of 3 shows it to have the 1,3,6-structure with a Re-Re bond length of 2.2318(3)Angstrom in accord with a Re-Re bond order of 3.5. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 37]