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Steric Influences in Octahedral Cohaloximes. The Crystal and Molecular Structure of trans-methylhis(dimethylglyoximato) (phosphite)cobalt(III) Complexs with Phosphite=P(OMe)2Ph and P(OMe)Ph2

Nevenka Bresciani-Pahor ; Istituto di Chimica, Universita di Trieste, 34127 Trieste, Italy
John D. Orbell ; Istituto di Chimica, Universita di Trieste, 34127 Trieste, Italy
Lucio Randaccio ; Istituto di Chimica, Universita di Trieste, 34127 Trieste, Italy

Sažetak

The crystal structures of the title compounds, (P(OMe)2Ph)Co(
DH)2Me (I) and (P(0Me)Ph2)Co(DH)2Me (II), are reported. Compound
I crystallizes in the orthorhombic system, space group Pbca,
with cell parameters a = 14.652(7), b = 26.45(1) and c = 11.330(6) A
and z = 8; compound II crystallizes in the monoclinic system, space
group P21 with cell parameters a = 9.423(7), b = 15.184(8), c = 8.948
(7) A and ~ = 100.50(9)0 , Z = 2. Both structures were solved by conventional
Patterson and Fourier methods and refined by the block
diagonal least-squares method to final R values of 0.033(1) and
0.034(II), using 2108 for I and 2063 for II independent reflections
with I > 30'(1). In both compounds the cobalt atom has a distorted
octahedral geometry, the two DH units occupying the equatorial
positions and Me and the P-ligand the axial ones. The Co-C and
Co- P bond lengths are 2.013(5) and 2.287(1) A in I and 2.019(6)
and 2.352(1) A in II, respectively. Linear correlation between Co-P
bond lengths and Tolman's cone angles in the series RaPCo(DH)2Me
is found, with the exception of the P(OMe)Ph2 derivative. Furthermore,
the linear relationship between the above Co-P distances
and those reported for analogous chloro-derivatives, already found
for phosphines, is valid for I but not for II.

Ključne riječi

Hrčak ID:

194113

URI

https://hrcak.srce.hr/194113

Datum izdavanja:

20.10.1984.

Posjeta: 858 *