Synthesis, spectroscopic and structural characterisation of copper, silverand gold complexes of the mixed P/O-donor ligand Ph2P(CH2)(2)O(CH2)(2)O(CH2)(2)PPh2

Reaction of L-1 (L-1 = Ph2P(CH2)(2)O( CH2)(2)O(CH2)(2)PPh2) with [Cu(MeCN)( 4)]PF6 or AgBF4 in CH2Cl2 solution yields the complexes [Cu(L-1)]PF6 and [A g(L-1)]BF4 respectively as white solids. Spectroscopic measurements are con sistent with coordination via the P-donors and the crystal structure of [Ag (L-1)]BF4 confirms that L-1 acts as a rrans-chelate giving an unusual examp le of approximately linear P-2-coordination at Ag(I) (angle P-Ag-P = 164.66 (4)degrees) and, despite the availability and proximity of the ether O atom s, these remain essentially uncoordinated (Ag ... O = 2.95 Angstrom) thus r eflecting the low affinity of the soft Ag(I) ion for hard O-donor ligands. [AuCl(tht)], L-1 and TIPF6 react in a 1:1:1 molar ratio in MeCN solution to yield the analogous Au(I) species [Au(L-1)]PF6, the structure of which als o shows linear P-2-coordination and once again the O-donors are non-coordin ating, at a distance of ca. 3.16 Angstrom from Au(I). The neutral dinuclear species [(AuCl)(2)(L-1) ] is readily formed by reaction of [AuCl(tht)] wit h L-1 in a 2:1 molar ratio in MeCN. Confirmation of the coordinated Cl liga nds comes from IR spectroscopy, nu(Au-Cl) = 324 cm(-1), and delta((31)p) wh ich is indicative of a PCl donor set at Au(I). This arrangement is confirme d in the solid state from the crystal structure. The related phosphathia co mplex [(AuBr)(2)(L-2)] (L-2 = Ph2P(CH2)(2)S(o-C6H4)S(CH2)(2)PPh2) is prepar ed similarly from [AuBr(tht)] and L-2 in MeCN solution and its structure re veals the AuBr units each coordinated to one P-donor and directed to the sa me side as the o-C6H4 unit. (C) 2000 Elsevier Science Ltd All rights reserv ed.