activation energy of ΔG‡ (298 K)=22.3±0.2 kcal mol−1. Complex 4a added [Ph3C+] to the butadiene ligand to yield the salt [(lig)Ni(η3-C3H4-CH2CPh3)+][B(C6F5)4−] (Z-12a), that proved isomerically stable under the applied reaction conditions. Similar reactions were carried out starting from the acenaphthylene 1,2-dione derived chelate bis(imine)Ni(butadiene) complex 4b. The systems 6, 7, 9 and 12 were found to
螯合的1,2-双(
亚胺)
镍(
丁二烯)配合物4a(由联乙酰与2,6-
二异丙基苯胺缩合而得的螯合
配体)在其末端碳原子上添加强
路易斯酸B(C 6 F 5)3。所述的
丁二烯配体,以产生偶极取代的π烯丙基型
甜菜碱络合物(LIG)的Ni [η 3 -C 3 H ^ 4 -CH 2 B(C 6 ˚F 5)3 ](ž -图6a)。在90°C下,动力学形成的产物与其E - 6a异构体平衡。同样,4a加入
硼路易斯酸(
吡咯基)B(C 6 F 5)2,得到相应的中性偶极π-烯丙基
甜菜碱络合物Z - 7a,在环境温度下与E - 7a缓慢平衡。复杂的的
丁二烯配体的质子化4A通过用中性布朗斯台德酸(
2H-吡咯)B处理(C达到6 ˚F 5)3,得到[(LIG)的Ni(η 3 -crotyl)+ ] [(
吡咯基) B(C 6 ˚F 5)3 - ]盐9A(制备时,Z- / E - 9a比率= 90:10。在298 K下,该盐重排为Z