Sol–gel derived hybrid materials as heterogeneous catalysts for the synthesis of N,N-dimethylformamide from supercritical carbon dioxide
作者:Oliver Kröcher、René A. Köppel、Alfons Baiker
DOI:10.1039/cc9960001497
日期:——
Hybrid materials derived from group VIII metal-chloro complexes of the type MCl(2)X(2) (M = Pt, Pd), MClX(3) (M = Rh, Ir) and especially RuCl(2)X(3) [X = Ph(2)P(CH2)(2)Si(OEt)(3), Me(2)P(CH2)(2)Si(OEt)(3)] by cocondensation with Si(OEt)(4) via a sol-gel process are highly active heterogeneous catalysts for the synthesis of N,N-dimethylformamide (dmf) from CO2, H-2 and dimethylamine under supercritical conditions, affording turnover numbers up to 110 800 at 100% selectivity.
Silica Hybrid Gel Catalysts Containing Group(VIII) Transition Metal Complexes: Preparation, Structural, and Catalytic Properties in the Synthesis ofN,N-Dimethylformamide and Methyl Formate from Supercritical Carbon Dioxide
作者:Oliver Kröcher、René A. Köppel、Michael Fröba、Alfons Baiker
DOI:10.1006/jcat.1998.2151
日期:1998.8
the organometallic complexes were immobilized as monomers. From all catalysts silica matrix stabilized ruthenium complexes exhibited highest activities at 100% selectivity in dmf synthesisfrom CO2, H2, and dimethylamine. The corresponding turnover frequency (TOF) of 1860 h−1exceeded those reported so far for heterogeneous catalysts by a factor of 600. In methylformatesynthesis, TOFs up to 115 h−1were
制备了溶胶-凝胶衍生的杂化材料,该杂化材料在多孔二氧化硅网络中包含(VIII)过渡金属配合物,并测试了由超临界二氧化碳,氢气和四氯化碳催化合成N,N-二甲基甲酰胺(dmf)和甲酸甲酯(mf)的能力。分别是二甲胺和甲醇/三乙胺。X = Ph 2 P(CH 2)2 Si(OEt)3和Y = Me 2 P(CH 2)2 Si(OEt)3双官能硅烷基醚膦用作配体,用于制备RuCl 2 X 3类型的配合物,RuCl 2 Y 3,MClX 3(M = Ir,Rh)和MC1 2 X 2(M = Pt,Pd)。甲硅烷基醚配合物通过与Si(OEt)4的共缩合而锚固在二氧化硅基质中。通过31 P和29 Si NMR光谱,扩展的X射线吸收精细结构(EXAFS),X射线衍射(XRD),透射电子显微镜(TEM)和氮气来表征杂化凝胶的结构和结构性质和氩的物理吸附。31P NMR光谱证实了Ru,Pt,Pd,Rh和Ir配