Photoacidic and Photobasic Behavior of Transition Metal Compounds with Carboxylic Acid Group(s)
作者:Ryan M. O’Donnell、Renato N. Sampaio、Guocan Li、Patrik G. Johansson、Cassandra L. Ward、Gerald J. Meyer
DOI:10.1021/jacs.6b00454
日期:2016.3.23
Excited state proton transfer studies of six Ru polypyridyl compounds with carboxylic acid/carboxylate group(s) revealed that some were photoacids and some were photobases. The compounds [Ru(II)(btfmb)2(LL)](2+), [Ru(II)(dtb)2(LL)](2+), and [Ru(II)(bpy)2(LL)](2+), where bpy is 2,2'-bipyridine, btfmb is 4,4'-(CF3)2-bpy, and dtb is 4,4'-((CH3)3C)2-bpy, and LL is either dcb = 4,4'-(CO2H)2-bpy or mcb =
六种具有羧酸/羧酸酯基团的 Ru 多吡啶基化合物的激发态质子转移研究表明,一些是光酸,一些是光碱。化合物[Ru(II)(btfmb)2(LL)](2+)、[Ru(II)(dtb)2(LL)](2+)和[Ru(II)(bpy)2(LL) )](2+),其中 bpy 是 2,2'-联吡啶,btfmb 是 4,4'-(CF3)2-bpy,dtb 是 4,4'-((CH3)3C)2-bpy,和LL 是 dcb = 4,4'-(CO2H)2-bpy 或 mcb = 4-(CO2H),4'-(CO2Et)-2,2'-bpy,被合成和表征。这些化合物在可见光区和室温光致发光 (PL) 中表现出强烈的金属到配体电荷转移 (MLCT) 吸收带,具有长 τ > 100 ns 激发态寿命。mcb 化合物具有非常相似的基态 pKa,为 2.31 ± 0.07,及其表征能够准确测定常用 dcb 配体的两个 pKa 值,pKa1