in solution. The crystal structures of all compounds but 3 have been determined and confirm that all form dimers with six-membered M2C2N2 rings in the chair conformation. The mass spectra indicate that the dimers are retained in the gas phase, and for 1 the molecular dynamics of ring inversion was monitored in solution by variable-temperature NMR spectroscopy, showing that the barrier for the inversion
二
甲基氨基甲基化合物(Me 2 AlCH 2 NMe 2)2(1),(Me 2 GaCH 2 NMe 2)2(2),(Me 2 InCH 2 NMe 2)2(3),(Me 2 AlCH 2 NMe 2) ·(MeClAlCH 2 NMe 2)(4),[ClAl(CH 2 NMe 2)2 ] 2(5)和[Al(CH通过使LiCH 2 NMe 2与相应的元素
氯化物或有机元素
氯化物反应来制备2 NMe 2)3 ] 2(6)。通过元素分析,NMR光谱法(1 H,13 C,27 Al)和质谱法进行表征。观察到异常低的27 Al NMR
化学位移为6(62 ppm),表明溶液中铝的配位数可能高于4。除3种化合物外,所有化合物的晶体结构均已确定,并确认所有化合物均形成具有六元M 2的二聚体C 2 N 2在椅子构象中环。质谱表明,二聚体保留在气相中,对于1,通过可变温度NMR光谱监测溶液中环转化的分子动力学,表明转化过程的障碍(9