Catalytic bond forming reactions promoted by amidinate, guanidinate and phosphaguanidinate compounds of magnesium
作者:Ryan J. Schwamm、Benjamin M. Day、Natalie E. Mansfield、William Knowelden、Peter B. Hitchcock、Martyn P. Coles
DOI:10.1039/c4dt01097c
日期:——
The synthesis and catalytic properties of a series of magnesium compounds consisting of monoanionic, N,N’-chelating ligands (N∩N = amidinates, guanidinates, phosphaguanidinates) is reported. The compounds were synthesized by (i) insertion of a carbodiimide into an existing Mg–C or Mg–N bond, or (ii) protonolysis of an organomagnesium compound by a neutral pre-ligand. Structural analyses of mono- or bis-(chelate) compounds with general formula Mg(N∩N)X(L)n and Mg(N∩N)2(L)n (X = halide, aryloxide, amide; L = Et2O, THF; n = 0, 1 or 2) have been performed and the influence that the ligand substituent patterns have on the solid-state structures has been probed. Selected examples of the compounds were tested as (pre)catalysts for the polymerization of lactide, the dimerization of aldehydes and the hydroacetylenation of carbodiimides.
报告了一系列镁化合物的合成及催化特性,这些化合物由单阴离子、N,N’-螯合配体(N∩N = 胺基脲化物、鸟嘌呤化物、膦酸鸟嘌呤化物)组成。化合物通过以下方法合成:(i) 在已有的Mg–C或Mg–N键中插入一个氨基亚胺,或(ii) 通过中性前配体对有机镁化合物进行质子解离。对具有一般公式Mg(N∩N)X(L)n和Mg(N∩N)2(L)n的单螯合或双螯合化合物(X = 卤素、芳氧化物、酰胺;L = Et2O,THF;n = 0、1或2)进行了结构分析,探讨了配体取代模式对固态结构的影响。选定的化合物作为乳酸酯聚合、醛类二聚化和氨基亚胺的水合炔化的(前)催化剂进行了测试。