The reaction of 2-diphenylphosphino-pyridine (1) with AgBF4 in an equimolar ratio affords the cyclic, dinuclear complex 2 with mixed P,N-coordination of the metal atoms. With two equivalents of 1 the 2:1 complexes 4a,b are formed which have the metal atoms solely Pcoordinated. The previously reported gold complex (3), an analogue of 2, or [Au(tht)2]ClO4 (tht = tetrahydrothiophen) also give the 2:1 complexes (5a,b) when treated with an excess of ligand 1. Addition of AgClO4 to a solution of 5a in acetone, or treatment of 4a with [Au(tht)2]ClO4 in dichloromethane, give the same mixed-metal complex 6, where the Au atoms are exclusively P-coordinated, while the Ag atoms are coordinated by the two pyridine nitrogen atoms. In the crystal there are also weak interactions of the perchlorate counterions with the silver atom. Addition of [Cu(MeCN)4]BF4 to compound 5b gives the Cu/Au-complex with P,P-coordinated gold and N,N-bonded copper centers. All products were characterized by standard analytical and spectroscopic techniques; the crystal structure of complex 6 was determined in a single crystal X-ray diffraction study.
将2-二苯基膦基吡啶(1)与AgBF4以等摩尔比反应,生成具有金属原子混合P,N配位的环状双核复合物2。使用两当量的1,形成了金属原子仅P配位的2:1配合物4a,b。 先前报道的金复合物(3)是2的类似物,或[Au(tht)2]ClO4(tht =四氢噻吩),当用过量的配体1处理时,也会产生2:1配合物(5a,b)。在丙酮中加入AgClO4到5a的溶液中,或在二氯甲烷中处理4a与[Au(tht)2]ClO4,会产生相同的混合金属配合物6,其中Au原子仅P配位,而Ag原子则由两个吡啶氮原子配位。在晶体中,过氯酸盐阴离子与银原子也有弱相互作用。向化合物5b中加入[Cu(MeCN)4]BF4,得到具有P,P配位金和N,N配位铜中心的Cu / Au配合物。所有产物均通过标准分析和光谱技术进行了表征;复合物6的晶体结构通过单晶X射线衍射研究确定。