arising from α- or β-H elimination processes were identified upon thermolysis. In addition to NMR studies of these compounds, cyclic voltammetry experiments show two oxidation processes; the Ta(III) ⇄ Ta(IV) couple is quasi-reversible, and the Ta(IV) → Ta(V) process is irreversible. Molecules of 5 exhibit a folded arene ligand with π-electron localization (diene−diyl structure) and normal ethyl ligands
一系列η的6 -hexamethylbenzene烷基和芳基配合物的
钽(III)由芳支撑并arenethiolate
配体已经制备,其特征在于,并与它们的卤化物类似物。因此,(η 6 -C 6我6)TA(OAR)2 Cl(上1中,Ar = 2,6--C 6 H ^ 3我
镨2)反应以将MeMgBr在低温下,得到(η 6 -C 6我6 TA(OAr)2 Me(3)。的低温烷基化(η 6 -C 6我6)TA(OAR)
氯2(2)与2当量的RMgBr形式(η 6 -C 6我6)TA(OAR)R 2(4,R =甲基; 5,R = ET),并用2当量的RLi得到(η的6 -C 6 Me 6)TA(OAr)R 2(6,R = CH 2 SiMe 3;7,R = Ph)。配合物3 − 7比其卤化物前体更稳定;经热解未鉴定出由α-或β-H消除过程产生的产物。除了这些化合物的NMR研究外,循环伏安法实验还显示出两