The role of 8-quinolinyl moieties in tuning the reactivity of palladium(II) complexes: a kinetic and mechanistic study
作者:Daniel O. Onunga、Deogratius Jaganyi、Allen Mambanda
DOI:10.1080/00958972.2019.1573994
日期:2019.2.1
and mechanism of chloride substitution from Pd(II) complexes, chlorobis-(2-pyridylmethyl)aminepalladium(II), 1, chloro-8-[(2-pyridylmethyl)amino]quinolinepalladium(II), 2, chloro-N-(2-pyridinylmethylene)-8-quinolinaminepalladium(II), 3, and chlorobis(8-quinolinyl)aminepalladium(II), 4, are reported. The labile chloride was substituted from the complexes by thiourea nucleophiles viz, thiourea (Tu), N,N′-dimethylthiourea
摘要 Pd(II)配合物氯代双-(2-吡啶基甲基)胺钯(II), 1, chloro-8-[(2-pyridylmethyl)amino]quinolinepalladium(II), 2, chloro-报道了 N-(2-吡啶基亚甲基)-8-喹啉胺钯 (II), 3 和氯双 (8-喹啉基) 胺钯 (II), 4。不稳定的氯化物被硫脲亲核试剂取代,即硫脲 (Tu)、N,N'-二甲基硫脲 (Dmtu) 和 N,N,N',N'-四甲基硫脲 (Tmtu)。使用停流分光光度法在甲醇中的准一级条件下监测反应作为浓度和温度的函数。所有反应都遵循速率定律 kobs = k2[Nu] 遵循 1 > 3 > 2 > 由于配位体的 8-喹啉基部分具有更强的 σ-供体效应,4 中的 4 表现出最慢的取代率,这使得 Pd 中心更富电子。这减缓了亲核试剂的亲核攻击。热力学参数(ΔH# 和 ΔS#)的值支持关联置换机制。DFT