Bond lengths phosphine complexes

Figure 2.16 Bond lengths in a rhodium(I) complex of a tridentate phosphine compared with...

Figure 2.56 Bond lengths in octahedral rhodium(III) complexes of dialkylphenyl phosphines.

They display the considerable trans-influence of hydride and aryl groups (the Pt-Cl bond lengths should be compared with the value of c. 2.31 A in PtCl4 ). The Pt-P bond lengths are more insensitive to the phosphine, but by synthesis of ds-Pt(PR3)(PR3)Cl2 [150] complexes, it has been possible to study the effect of electron-withdrawing substituents on the Pt-P bond, as well as on the trans-influence of the phosphine (Figure 3.94). 

Careful comparison of Pt-P bond lengths for the series trany-Pt(Pcy3)2X2 (X = H, Cl, Br, I) with those for p-any-Pt(PR3)2X2 (PR3 = PMe3 or PEt3) shows a more definite increase in Pt-P with anion size for the cyclohexyl-phosphine complexes (Table 3.16) believed to be owing to intermolecular X- H and X- C non-bonded interactions arising from overcrowding [151]. 

A remarkably stable, deep red Ni° stannylene complex, [Ni(1068)4l, has been prepared by the reaction of [Ni(l,5-cyclooctadiene)2] with (1068) in toluene at —78 °C. 70 In spite of the bulkiness of (1068) and the known tendency of analogous Ni° phosphine complexes to dissociate in solution, [Ni(1068)4] remains intact in solution and, moreover, melts at 178-180 °C without decomposition. X-ray crystallography shows tetrahedral geometry about the nickel atom, with Ni—Sn bond lengths of 2.3898(2)-2.399(2) A. 

Di- x-bromobis[diethylenethioureatellurium(II)] dibromide, 35 294-295 Dibromobis(phosphine)nickel(Il) complex, bond length changes in spin state transition, 32 6... 

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