Trimethylstannane derivatives of cobalt(I); synthesis and NMR spectroscopy. The crystal structures of [Co(Me3Sn)(CO)3L] (L = PPh3, AsPh3)
摘要:
The Na/Hg reductive cleavage of the cobalt-cobalt bond in Co2(CO)6L2 (L = PPh3, P(OPh)3, AsPh3) and subsequent reaction with Me3SnCl, afforded the five-coordinate complexes Co(Me3Sn)(CO)3L (L = PPh3, P(OPh)3, AsPh3). The intermediate sodium salts Na[Co(CO)3L] are unstable and were not isolated. The P-31, Sn-119, C-13 and H-1 NMR spectra were recorded and are discussed. Crystal structure analyses of [Co(Me3Sn) (CO)3L] (L = PPh3, AsPh3) revealed, in both cases, a trigonal bipyramidal geometry with the trimethyl tin and the triphenyl phosphine/arsine in the two axial positions.
Characterization of the Solid−Solid Phase Transition of Co2(CO)6(AsPh3)2
摘要:
The dimeric Co-2(CO)(6)(AsPh3)(2) molecule contains an unsupported Go-Co bond axial arsines, and equatorial carbonyls. At room temperature, the molecule crystallizes in the R (3) over bar space group [a = 15.473(3) Angstrom, c = 14.240(2) Angstrom] packing in chains along c which are hexagonally arranged in the ab plane. When the temperature is lowered, no significant changes are found in the molecular structure until a second-order phase transition [T-c = 206(3) K] occurs by doubling the c axis [at T = 123 K a = 15.233(4) Angstrom, c = 28.440(6) Angstrom, space group R (3) over bar]. The major molecular conformational changes related to the phase transition are the rotations of Co(CO)(3) and AsPh3 fragments about the 3-fold axes and those of the phenyls about their As-C bond. X-ray studies at 16 different temperatures have been performed in order to describe the details of the small continuous structural changes that occur in the low-temperature phase.
Chemistry of methinyltricobalt enneacarbonyls. Part V. Tertiary phosphine and arsine derivatives
作者:T. W. Matheson、B. H. Robinson、W. S. Tham
DOI:10.1039/j19710001457
日期:——
Mono-, di-, and tri-substituted tertiary phosphine and arsine derivatives of methinyltricobaltenneacarbonyls have been prepared. The co-ordination behaviour of the cluster is determined by the apical substituent Y, and the stereochemistry adopted is one which minimizes nonbonded carbonyl interactions. Thus the majority of mono-substituted complexes have the same structure as MeCCo3(CO)8Ph3P but other
Infrared spectra of some derivatives of octacarbonyldicobalt
作者:A. R. Manning
DOI:10.1039/j19680001135
日期:——
A number of cobalt carbonyl derivatives of the type [L Co(CO)3]2[L = Et3P, Bu3P, PhMe2P, PhEt2P, Ph3P, (MeO)3P, (PhO)3P, Et3As, or Ph3As] have been prepared, and their infraredspectra investigated in the range 225–4000 cm.–1. Absorption bands due to the vibrations of the Co2(CO)6 moiety have been identified and assigned where possible.