New diamino-diheterophenol ligands coordinate iron(<scp>iii</scp>) to make structural and functional models of protocatechuate 3,4-dioxygenase
作者:Joshua R. Farrell、Jonathan A. Niconchuk、Peter R. Renehan、Christine S. Higham、Eric Yoon、Mark V. Andrews、Janet L. Shaw、Anil Cetin、James Engle、Christopher J. Ziegler
DOI:10.1039/c3dt53431f
日期:——
Three five-coordinate Fe(iii) complexes were prepared that are functional and structural models for the enzyme Protocatechuate 3,4-dioxygenase (3,4-PCD).
Dimeric μ-oxo bridged molybdenum(vi) dioxo complexes as catalysts in the epoxidation of internal and terminal alkenes
作者:Martina E. Judmaier、Chris H. Sala、Ferdinand Belaj、Manuel Volpe、Nadia C. Mösch-Zanetti
DOI:10.1039/c3nj00115f
日期:——
The preparation of the tridentate phenol based amine ligands HL1–HL4 is achieved via a convenientone-potsynthesis by reductive amination in quantitative yield in an autoclave under 7 bar H2 gas. Reaction of [MoO2(acac)2] and the corresponding ligand HLX (X = 1, 2 and 4) in methanol–H2O results in the formation of orange to red dimeric μ-oxo bridged [MoO2(LX)}2(μ-O)] (X = 1, 2 and 4) complexes 1–3
三齿酚基胺配体HL 1 -HL 4的制备是通过在7 bar H 2气体下,在高压釜中以定量收率进行还原性胺化,通过方便的一锅合成来实现的。[的MoO的反应2(ACAC)2 ]和相应的配体HLX(X = 1,2和4)在甲醇–高氧2导致形成橙色至红色二聚体μ氧桥连[的MoO 2(LX)} 2(μ-O)](X = 1,2和4)络合物1-3以高收率和高的纯度。配合物1-3对空气和空气稳定水。两个配体均通过fac模式通过侧链上的酚O原子,胺N原子和第三个供体原子(金属原子为1的OMe,金属原子为2和3的NMe 2)配位至金属中心。钼原子通过桥连的μ-氧代部分相互连接,这是通过配合物2和3的X射线衍射分析证实的。使用TBHP作为氧化剂,已经在几种内部和末端烯烃的环氧化中测试了所有配合物。取决于底物的性质,以中等至良好的产率和高的选择性获得环氧化物。在环氧化中环辛烯观察到复合物1的TOF = 467 h