一类三氮唑钌配合物作为可见光催化剂用于四氢咪唑类化合物的合成

Triazole ruthenium complexes as visible light photocatalysts for the synthesis of tetrahydroimidazole derivative

可见光催化是近年来的研究热点之一,受到了合成化学工作者的广泛关注。将含有三氮唑片段为配体的钌配合物作为可见光催化剂的相关研究鲜有文献报道,因此,本研究由简单的底物出发,通过铜催化的乌尔曼偶联反应和Click反应策略实现三氮唑配体的合成,随后配体和钌二联吡啶的光催化剂前体配位,分别以70%~83%的收率完成一系列光催化剂的合成,并通过X射线衍射和核磁共振表征结构。最后,将三氮唑钌配合物用于可见光诱导的光反应中,该系列催化剂中有3种具有催化活性,其中最高能以64%的收率得到四氢咪唑类化合物。

Visible light induced photocatalysis,as one of the hot research topics,has attracted extensive attention of synthetic chemists recently.Photocatalyst that centered on the ruthenium containing triazole as ligand was still blank for the visible light induced organic synthesis.In this paper,triazole ligands were delivered by copper catalyzed Ullman cross-coupling or Click reaction with commercially available starting materials.The photocatalysts were finally afforded by coordination of the ligands with the ruthenium 2,2'-bipyridine complex precursor in yields range from 70%to 83%,and the structures were characterized by X-ray crystal diffraction and nuclear magnetic resonance spectroscopy.The photocatalysts were then applied to the visible light induced photoreaction.At the standard conditions,three of them exhibited catalytic activity,the highest yield of tetrahydroimidazole was 64%.