The singlet state potential energy curve of the reaction: Ni (d1 0 1S)+ CH 4 → NiCH 2 + H 2, and geometric structures and vibrational frequencies of all intermediates and transition states in the reaction path were s...The singlet state potential energy curve of the reaction: Ni (d1 0 1S)+ CH 4 → NiCH 2 + H 2, and geometric structures and vibrational frequencies of all intermediates and transition states in the reaction path were studied by B3LYP method. In the reaction, an atom molecule complex NiCH 4 acting as precursor in the breaking of C-H bond was predicted. For NiCH 4, a frequency of 2988 cm -1 is typical of methane molecularly adsorbed on Ni. A nickel hydrido methyl complex HNiCH 3 is formed upon the very low barrier insertion of Ni 0 into a C-H bond of CH 4. A dihydrogen complex of atom nickel carbene (H 2)NiCH 2 proceeds from the migration of α hydrogen from carbon to metal with considerably large barrier, indicating that this is the rate determining step in the whole reaction. In general, the overall reaction is mildly exothermic by 1.6 kJ·mol -1 relative to Ni(d1 0 1S) + CH 4 reactants.展开更多
目的利用有机膦支持的低价钴配合物对二茂铁Schiff碱衍生物C-H键活化进行研究。方法采用标准的Schlenk无水无氧操作技术,常温下利用(四甲基膦)甲基钴同二茂铁单甲醛缩萘氨反应,得到了一种新型的异双核的化合物,并利用IR,1 H NMR以及X-ra...目的利用有机膦支持的低价钴配合物对二茂铁Schiff碱衍生物C-H键活化进行研究。方法采用标准的Schlenk无水无氧操作技术,常温下利用(四甲基膦)甲基钴同二茂铁单甲醛缩萘氨反应,得到了一种新型的异双核的化合物,并利用IR,1 H NMR以及X-ray单晶衍射对目标化合物进行了表征。结果显示该化合物属于单斜晶系,P21/n空间群,晶胞参数a=10.692(2),b=14.273(3),c=19.719(4),β=99.58(3)°;中心钴原子与3个磷原子、亚氨基氮原子以及萘环上的碳原子成键,呈5配位的三角双锥几何构型。结论利用有机膦支持的低价钴配合物成功实现了二茂铁甲醛缩萘胺sp2杂化的C-H键的活化。展开更多
文摘The singlet state potential energy curve of the reaction: Ni (d1 0 1S)+ CH 4 → NiCH 2 + H 2, and geometric structures and vibrational frequencies of all intermediates and transition states in the reaction path were studied by B3LYP method. In the reaction, an atom molecule complex NiCH 4 acting as precursor in the breaking of C-H bond was predicted. For NiCH 4, a frequency of 2988 cm -1 is typical of methane molecularly adsorbed on Ni. A nickel hydrido methyl complex HNiCH 3 is formed upon the very low barrier insertion of Ni 0 into a C-H bond of CH 4. A dihydrogen complex of atom nickel carbene (H 2)NiCH 2 proceeds from the migration of α hydrogen from carbon to metal with considerably large barrier, indicating that this is the rate determining step in the whole reaction. In general, the overall reaction is mildly exothermic by 1.6 kJ·mol -1 relative to Ni(d1 0 1S) + CH 4 reactants.
文摘目的利用有机膦支持的低价钴配合物对二茂铁Schiff碱衍生物C-H键活化进行研究。方法采用标准的Schlenk无水无氧操作技术,常温下利用(四甲基膦)甲基钴同二茂铁单甲醛缩萘氨反应,得到了一种新型的异双核的化合物,并利用IR,1 H NMR以及X-ray单晶衍射对目标化合物进行了表征。结果显示该化合物属于单斜晶系,P21/n空间群,晶胞参数a=10.692(2),b=14.273(3),c=19.719(4),β=99.58(3)°;中心钴原子与3个磷原子、亚氨基氮原子以及萘环上的碳原子成键,呈5配位的三角双锥几何构型。结论利用有机膦支持的低价钴配合物成功实现了二茂铁甲醛缩萘胺sp2杂化的C-H键的活化。
