New Molecular Transformations Mediated by Bioinspired Catalysts

我们一直对维生素B_<12>依赖性酶感兴趣，这些酶涉及作为催化中心的钴物种，并涉及疏水性维生素B_<12>，七甲基钴氰酸酯高氯酸盐，其具有酯基代替天然存在的维生素B_的外围酰胺部分<12>。为了构建良好的催化体系，我们制备了多种具有维生素B_活性的纳米材料<12>。从绿色化学的观点来看，这些生物启发的催化剂非常有趣。1，1-双（4-氯苯基）-2，2，2-三氯乙烷（DDT）的特点是具有显著的杀虫特性，尽管已知其对人类健康和野生动物的有害影响，但在过去几十年中已在全世界使用。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_功能的仿生催化剂能有效降解DDT<12>。这类具有维生素B_功能的仿生催化剂<12>不仅可用于有机卤化物污染物的降解，还可用于自由基中间体的有机合成。

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.