Synthesis, Characterization and Catalytic Activity of Metal Complexes of New Schiff Bases Derived from Biphenyl-diamine

在前面的项目We 1561/21-1和We 1561/21-2中，制备了四齿2，2 '-双（水杨基氨基）-4，4'-二甲基-1，1 '-联苯席夫碱。它的钾络合物显示出轮状八聚体，其仅微溶于普通有机溶剂。亚水杨基上的甲氧基取代基显著降低了聚合度，提高了溶解性。四齿2，2 '-双（亚水杨基氨基）-4，4'-二甲基-1，1 '-联苯配体的转移通过该钾盐与氯化钛（IV）的复分解方法顺利发生，但形成两种异构体，其中剩余的氯原子具有顺式和反式排列。在这项提案中，我们要求提供资金，以准备和研究钇（III）络合物。此外，我们打算用两个溴原子在6，6 '-位取代联苯片段，以确保钛（IV）衍生物中的顺式排列。初步研究允许阐明这种配合物在催化加氢官能化反应中的适用性。

In the preceding projects We 1561/21-1 and We 1561/21-2, tetradentate 2,2’-bis(salicylideneamino)-4,4'-dimethyl-1,1’-biphenyl Schiff bases were prepared. Its potassium complex shows a wheel-shaped octamer which is only sparingly soluble in common organic solvents. Methoxy substituents at the salicylidene subunits significantly reduce the aggregation degree and enhance solubility. The transfer of the tetradentate 2,2’-bis(salicylideneamino)-4,4'-dimethyl-1,1’-biphenyl ligand occurs smoothly via a metathetical approach of this potassium salt with titanium(IV) chloride but two isomers are formed with cis- and trans-arrangement of the remaining chlorine atoms. In this proposal, we ask for funding to prepare and study the yttrium(III) complex. Furthermore, we intend a substitute the biphenyl fragment with two bromine atoms in 6,6'-positions to ensure a cis-arrangement in titanium(IV) derivatives. Preliminary studies allow to elucidate the suitability of such complexes in catalytic hydrofunctionalization reactions.