New Molecular Transformations Mediated by Bioinspired Catalysts

我们一直对维生素B_<12>依赖的酶感兴趣，涉及钴种作为催化中心，并处理疏水性维生素B_<12>，高氯酸七甲基共青酯，它具有酯基代替天然维生素B_<12>的外周酰胺部分。为了构建一个良好的催化体系，我们制备了多种维生素B_<12>活性的纳米材料。从绿色化学的角度来看，这些生物催化剂是非常有趣的。1,1-二（4-氯苯基）-2,2,2-三氯乙烷（滴滴涕）的特点是具有明显的杀虫特性，尽管已知其对人类健康和野生动物有危险影响，但在过去几十年中，滴滴涕一直在世界范围内使用。由于最近的环境问题，迫切需要有效的方法来降解土壤中积累的这种氯化化合物。具有维生素B_<12>功能的仿生催化剂对DDT有较好的降解效果。这种具有维生素B_<12>功能的仿生催化剂不仅可以降解有机卤化物污染物，还可以通过自由基中间体进行有机合成。

We have been interested in vitamin B_<12>-dependent enzymes, involving the cobalt species as a catalytic center, and dealing with a hydrophobic vitamin B_<12>, heptamethyl cobyrinate perchlorate, which has ester groups in place of the peripheral amide moieties of the naturally occurring vitamin B_<12>. In order to construct a good catalytic system, we prepared various nanomaterials with vitamin B_<12> activities. These bioinspired catalysts are very interesting from the viewpoint of green chemistry. 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) is characterized by a pronounced insecticidal property and has been used worldwide for the last several decades despite its known hazardous effects on human health and wildlife. Because of recent environmental concerns, there is pressing need for efficient methods for degradation of such chlorinated compounds accumulated in the soil. DDT was degradated effectively by the bio-inspired catalysts with vitamin B_<12> function. Such bioinspired catalysts with vitamin B_<12> functions can apply not only the degradation of organic halide pollutants but also the organic synthesis via radical intermediates.