synthesized from the corresponding neutral compounds. In the former complex, the metal ion is coordinated to both nitrogen atoms, forming a constrained four-membered ring, whereas the latter complex forms a five-membered ring as the metal ion coordinates preferentially to the phosphorus
2-(
二苯基膦氨基)
吡啶和N,2-双(
二苯基膦基)
苯胺的
锂配合物已由相应的中性化合物合成。在前一种配合物中,
金属离子与两个氮原子配位,形成一个受约束的四元环,而后一种配合物形成一个五元环,因为
金属离子优先与
磷配位