Summary
A series of three-coordinate bis(dialkylphosphinomethyl)benzo[c]phenanthreneAg (1) ClO,] have been determined by X-ray diffraction. The Ag atom in these complexes shows distorted trigonal geometry. Selected bond lengths and angles are as follows: Ag-P = 2.463(4) A and 2.433(5) A, P-Ag-P = 141.6(2)" in the bromo complex, Ag-P = 2.457(2) A and 2.427(2) A, P-Ag-P = 142.6(1)" in the chloro complex, and Ag-P = 2.394(2) and 2.393(2) A, P-Ag-P = 161.5(1)" in the perchlorato complex.1. Introduction. -Three-coordinate complexes of Ag(1) with tertiary phosphine ligands normally have trigonal micro-geometry about the metal atom. As the ligand 2,11-bis(diphenylphosphinomethyl)benzo[c]phenanthrene (la) has been shown to prefer spanning trans-positions in square-planar and octahedral complexes [2], it was expected that its complexes with Ag(1) would exhibit considerable distorsion from 120" angles. Indeed, crystallographic studies of the complexes [M(la)Cl] (M = Cu(I), Ag(1) and Au(1)) have shown that although the metal atoms are three-coordinate, the P-M-P angles are 132, 141 and 176", respectively [3]. 3'P-NMR studies for the complexes [Ag(la)X], X = BF,, NO,, C1, I, in solution have shown that changes in the values 'J('07Ag, ,'P) correlate with the capability of the anion, X, to coordinate to silver [4]. Moreover, for X = ClO,, NO,, SnC1, (bound via Cl), this coupling constant correlates with the bond separations (Ag-P) and the bond angles P-Ag-P [5] in a way similar to