NNN型配体及其钨卡宾配合物合成

Synthesis of NNN-type ligand and its tungsten carbene complex

将4,4′-二甲基二苯胺依次经硝化和还原后,合成了双(4-甲基-2-氨基苯基)胺.此化合物与三苯基氯甲烷进行N-烷基化反应,高产率地得到了一种新的氨基-NNN钳形配体2,2′-二(三苯甲基氨基)-4,4′-二甲基二苯胺.该配体在空气中稳定,且能与(t-BuO)_(3)W≡CPh反应形成一种新型的钨卡宾配合物.通过核磁共振、X-射线单晶衍射等方法对该卡宾配合物研究发现,配体的3个N原子并未全部参与配位,而是有1个N原子取代基上的苯环参与了配位.通过DFT计算,发现NNC型配合物比NNN型配合物能量更低.

Bis(4-methyl-2-aminophenyl)amine was synthesized by nitration and reduction of 4,4′-dimethyldiphenylamine.After N-alkylation of this compound with triphenylchloromethane,a new amino NNN-pincer ligand,2,2′-bis(triphenylmethylamino)-4,4′-dimethyldiphenylamine was obtained in high yield.This ligand is stable in air and can coordinate with(t-BuO)_(3)W≡CPh to form a new tungsten carbene complex.The NMR and X-ray single crystal diffraction show that not all the three N atoms of the ligand coordinate to the metal,but the benzene of one N atom′s substituent coordinates.DFT calculation proves that the energy of NNC-type complex is lower than the energy of NNN-type complex.