A new carbene ruthenium complex, 1,3-bis（2,6-dimethylphenyl）-4,5-dihydroimidazol-2-ylidene）（PPh3）Cl2-Ru=CHPh, was synthesized and used as catalyst for the metathesis of 1-hexene. The resulting complex exhibited v...A new carbene ruthenium complex, 1,3-bis（2,6-dimethylphenyl）-4,5-dihydroimidazol-2-ylidene）（PPh3）Cl2-Ru=CHPh, was synthesized and used as catalyst for the metathesis of 1-hexene. The resulting complex exhibited very high catalytic activity whose TOF is up to 6680 h^-1. However, at the same time significant olefin isomerization was observed and could be surpressed by changing reaction conditions, such as temperature, time, alkene/Ru molar ratio and solvent.展开更多
A series of novel calix[4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by ~1H NMR,^（13）C NMR and ESI-HRMS.Th...A series of novel calix[4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by ~1H NMR,^（13）C NMR and ESI-HRMS.Their complexation property towards cesium ion was studied by ^1H NMR technique.Two-phase extraction of alkali metal ions using UV-vis spectroscopy revealed remarkably different extractabilities.These results indicate that the complexation capacities towards cesium ions can be tuned and controlled through cooperative regulation of the strain of the loop and conformational change of calixcrown skelton.展开更多
A ruthenium carbene complex containing a Zn-porphyrin ligand has been developed. The complex was charac- terized by 1H NMR, IR, HRMS and elemental analysis. The catalytic activity of the ruthenium carbene complex for ...A ruthenium carbene complex containing a Zn-porphyrin ligand has been developed. The complex was charac- terized by 1H NMR, IR, HRMS and elemental analysis. The catalytic activity of the ruthenium carbene complex for olefin metathesis reactions was also investigated. The complex exhibited excellent performance for both ring-closing and cross metathesis reactions at 35 ℃.展开更多
A Grubbs-Hoveyda pre-catalyst having a trimeric resting state based on 2,4,6-trichloro-1,3,5-triazine was syn-thesized and the complex was characterized by NMR,HRMS and elemental analysis.The activity of this complex ...A Grubbs-Hoveyda pre-catalyst having a trimeric resting state based on 2,4,6-trichloro-1,3,5-triazine was syn-thesized and the complex was characterized by NMR,HRMS and elemental analysis.The activity of this complex for ring-closing metathesis(RCM)was investigated.The catalytic system possesses high catalytic activity for many different olefin substrates.展开更多
文摘A new carbene ruthenium complex, 1,3-bis（2,6-dimethylphenyl）-4,5-dihydroimidazol-2-ylidene）（PPh3）Cl2-Ru=CHPh, was synthesized and used as catalyst for the metathesis of 1-hexene. The resulting complex exhibited very high catalytic activity whose TOF is up to 6680 h^-1. However, at the same time significant olefin isomerization was observed and could be surpressed by changing reaction conditions, such as temperature, time, alkene/Ru molar ratio and solvent.
基金financially supported by Institute of Nuclear Physics and Chemistry of CAEP(NoHG2008061)
文摘A series of novel calix[4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by ~1H NMR,^（13）C NMR and ESI-HRMS.Their complexation property towards cesium ion was studied by ^1H NMR technique.Two-phase extraction of alkali metal ions using UV-vis spectroscopy revealed remarkably different extractabilities.These results indicate that the complexation capacities towards cesium ions can be tuned and controlled through cooperative regulation of the strain of the loop and conformational change of calixcrown skelton.
基金This work was supported by the National Natural Science Foundation of China （grant No. 21102102）.
文摘A ruthenium carbene complex containing a Zn-porphyrin ligand has been developed. The complex was charac- terized by 1H NMR, IR, HRMS and elemental analysis. The catalytic activity of the ruthenium carbene complex for olefin metathesis reactions was also investigated. The complex exhibited excellent performance for both ring-closing and cross metathesis reactions at 35 ℃.
基金supports from NSFC(Nos.21102102,21072149,20872108)are gratefully acknowledged.
文摘A Grubbs-Hoveyda pre-catalyst having a trimeric resting state based on 2,4,6-trichloro-1,3,5-triazine was syn-thesized and the complex was characterized by NMR,HRMS and elemental analysis.The activity of this complex for ring-closing metathesis(RCM)was investigated.The catalytic system possesses high catalytic activity for many different olefin substrates.
