Synthesis and structural characterization of {mu(3)-H(Ph)C=C}FeCo2(CO)(7)dppm (dppm = Ph2PCH2PPh2) and {mu(3)-H(Ph)C=C} FeCo2(CO)(9-n)L-n [L = PPh3 (n=1, 2), AsPh3 (n=1)]

The new mixed-metal clusters {mu (3)-H(Ph)C=C}FeCo2(CO)(7)dppm (dppm = Ph2P CH2PPh2) (1) and {mu (3)-H(Ph)C=C}FeCo2(CO)(9)-nL(n) [L = PPh3, n = 1 (2), n = 2 (3); AsPh3, n = 1 (4)] have been synthesized by facile substitution r eactions. The molecular structures of 1, 2 and 4 have been determined by si ngle-crystal X-ray analysis; dppm replaces two equatorial carbonyls from tw o Co(CO)(3) groups, and PPh3 and AsPh3 replace one equatorial carbonyl from a Co(CO)(3) group, respectively. The new compounds were characterized by I R, H-1-, P-31- (for 1-3) NMR and MS. Cyclic voltammetric behavior for 1, 2 and 4 was investigated, and the results show the order of sigma -donator ab ility is CO < PPh3 < AsPh3 < dppm. (C) 2001 Elsevier Science BN. All rights reserved.