Group 11 Metal Chemistry of a Tetradentate Ligand, Phenylene-1,4-diaminotetra(phosphonite), p-C6H4[N{P(OC6H4OMe-o)2}2]2

Abstract

The Cu(I), Ag(I), and Au(I) chemistry of a tetradentate ligand (phenylene-1,4-diaminotetra(phosphonite), p-C(6)H(4)[N{P(OC(6)H(4)OMe-o)(2)}(2)](2) (P(2)NPhiNP(2)) (1)) is described. The flexional conformations in 1 leads to interesting structural variations in transition-metal complexes. The reaction of 1 with 4 equiv of CuX (where X = Br and I) produce the tetranuclear complexes, [{Cu(2)(mu-X)(2)(NCCH(3))(2)}(2)(mu-P(2)NPhiNP(2))] (where X = Br (2) or X = I (3)) in quantitative yield. Treatment of 3 with an excess of pyridine, 2-(piperazin-1-yl)pyrimidine, and pyrazole yielded the tetra-substituted derivatives, [{Cu(2)(mu-I)(2)(L)(2)}(2)(mu-P(2)NPhiNP(2))] (where L = pyridine (4), 2-(piperazin-1-yl)pyrimidine (5), or pyrazole (6)). Similar reactions of 3 with 1,10-phenanthroline (phen) and 2,2'-bipyridine in a 1:2 molar ratio afford the disubstituted derivatives, [(Cu(2)(mu-I))(2)I(2)(phen)(2)(mu-P(2)NPhiNP(2))] (7) and [(Cu(2)(mu-I))(2)I(2)(bipy)(2)(mu-P(2)NPhiNP(2))] (8). The o-methoxyphenoxy substituents on phosphorus in complexes 5 and 7 adopt approximately parallel planar conformations and contain lattice solvents. The reaction of 3 with 1,4-diazabicyclo[2.2.2]octane (DABCO) in a 1:2 molar ratio in a dichloromethane-acetonitrile mixture leads to the formation of an ionic complex [N(CH(2)CH(2))(3)N(+)CH(2)Cl](2)[(Cu(2)(Cl)(I)(2))(2)(NCCH(3))(2)(mu-P(2)NPhiNP(2))](2-) (9), as a result of the chloromethylation of DABCO. Treatment of 1 with 4 equiv of AgClO(4) produces [{Ag(2)(mu-ClO(4))(2))(2)(C(4)H(8)O)(2)}(2)(mu-P(2)NPhiNP(2))] (10). Displacement of perchlorate ions in 10 by PhN{P(OC(6)H(4)OMe-o)(2)}(2) (PNP) or 2,2'-bipyridine yielded [(mu-PNP)(2)Ag(2)(mu-P(2)NPhiNP(2))Ag(2)(mu-PNP)(2)](ClO(4))(4) (11) and [{Ag(2)(bipy)(2)}(2)(mu-P(2)NPhiNP(2))](ClO(4))(4) (12), respectively. The similar reaction of 1 with 2 equiv of AgOTf, in the presence of 4,4'-bipyridine, gave a three-dimensional Ag(I) coordination polymer, [{Ag(2)(C(10)H(8)N(2))(2)(CH(3)CN)(2)}(2)(P(2)NPhiNP(2))](n)(OTf)(4n) (13). The reactions of 1 with [AuCl(SMe(2))], in appropriate ratios, afford the tetranuclear and dinuclear complexes, [(Au(2)Cl(2))(2)(mu-P(2)NPhiNP(2))] (14) and [(AuCl)(2)(P(2)NPhiNP(2))] (15). Complex 14 undergoes moisture-assisted P-N bond cleavage in the presence of PhN{P(OC(6)H(4)OMe-o)(2)}(2) to give [p-NH(2)C(6)H(4)N{P(OC(6)H(4)OMe-o)(2)}(2)Au(2)Cl(2)] (17) and [PhN{P(OC(6)H(4)OMe-o)(2)}(2)Au(2)Cl(2)]. The structures of the complexes 5, 7-10, 12-15, and 17 are confirmed by single-crystal X-ray diffraction studies.