Smucker Bradley W, Vanstipdonk Michael J, Eichhorn David M
Department of Chemistry, Wichita State University, Wichita, KS 67260-0051, United States.
J Inorg Biochem. 2007 Oct;101(10):1537-42. doi: 10.1016/j.jinorgbio.2007.06.042. Epub 2007 Aug 14.
The use of 2,2'-dithiodibenzaldehyde (DTDB) as a reactant for incorporating thiolate donors into the coordination sphere of a transition metal complex without the need for protecting groups is expanded to include the synthesis of complexes with pentadentate ligands. The ligand N,N'-bis(thiosalicylideneimine)-2,2'-thiobis(ethylamine) (tsaltp) is synthesized at a cobalt center by the reaction of DTDB with a Co complex of thiobis(ethylamine). The resulting Co complexes are thus coordinated by the N(2)S(3) pentadentate ligand through two imine N atoms, two thiolate S atoms, and one thioether S atom. A dimeric, bis-thiolate-bridged complex (1) is isolated and converted to a monomeric CN adduct (2) by treatment with KCN. The N(2)S(3) coordination environment provided by the tsaltp ligand is similar to that provided by the protein donors at the active site of the nitrile hydratase enzymes, with 2 being the first octahedral Co complex reported with such a coordination sphere.
2,2'-二硫代二苯甲醛（DTDB）作为一种反应物，可在无需保护基团的情况下将硫醇盐供体引入过渡金属配合物的配位球中，其应用范围得以扩展，包括合成具有五齿配体的配合物。通过DTDB与硫代双（乙胺）的钴配合物反应，在钴中心合成了配体N,N'-双（硫代水杨醛亚胺）-2,2'-硫代双（乙胺）（tsaltp）。所得的钴配合物因此通过两个亚胺N原子、两个硫醇盐S原子和一个硫醚S原子由N(2)S(3)五齿配体配位。分离得到一种二聚体、双硫醇盐桥联配合物（1），并用KCN处理将其转化为单体CN加合物（2）。tsaltp配体提供的N(2)S(3)配位环境与腈水合酶活性位点处蛋白质供体提供的配位环境相似，配合物2是报道的第一个具有这种配位球的八面体钴配合物。
