An efficient method for the selective hydrogenation of a series of α,β-epoxyketones to β-hydroxyketones using catalytic amount of two sulfinyl analogues of NAD^＋ model compounds is reported. The lack of any diaste...An efficient method for the selective hydrogenation of a series of α,β-epoxyketones to β-hydroxyketones using catalytic amount of two sulfinyl analogues of NAD^＋ model compounds is reported. The lack of any diastereoselectivity for the formation of β-hydroxyketones with optically pure sulfinyl analogue of NAD^＋ model supports the radical mechanism proposed previously.展开更多
A polyethylene glycol (PEG)-supported NADH model as a novel organic reductant was designed and synthesized. The reductions of various α,β-unsaturated ketones by the PEG-supported NADH model were examined,and the res...A polyethylene glycol (PEG)-supported NADH model as a novel organic reductant was designed and synthesized. The reductions of various α,β-unsaturated ketones by the PEG-supported NADH model were examined,and the results showed that the reductions completely and quickly proceed with no catalyst at ambient temperature. The main advantages of this liquid-like PEG-supported NADH model are easy workup,and an optimal potential for recycling use and solvent-free for use in reactions.展开更多
The rate constant and kinetic isotopic effect(k H/k D) of the reduction of 2-bromo-1-phenylethylidenemalononitrile with NADH model were determined through NMR spectroscopy. The results were consistent with that the hy...The rate constant and kinetic isotopic effect(k H/k D) of the reduction of 2-bromo-1-phenylethylidenemalononitrile with NADH model were determined through NMR spectroscopy. The results were consistent with that the hydride transfer step of the reaction which was the rate-determining step, and were comparable to the results obtained through UV-Vis Spectroscopy reported previously.展开更多
基金Project supported by the National Natural Science Foundation of China （No. 20072036） and the Specialized Research Fund for the Doctoral Program of Higher Education of China.Acknowledgment We would like to thank Professor Yun-Dong Wu of the Hong Kong University of Science and Technology and Peking University for helpful advice.
文摘An efficient method for the selective hydrogenation of a series of α,β-epoxyketones to β-hydroxyketones using catalytic amount of two sulfinyl analogues of NAD^＋ model compounds is reported. The lack of any diastereoselectivity for the formation of β-hydroxyketones with optically pure sulfinyl analogue of NAD^＋ model supports the radical mechanism proposed previously.
基金supported by the National Basic Research Program of China (2004CB719905)the National Natural Science Foun-dation of China (20832004,20472038,20721062 and 20672060)the 111 Project (B06005)
文摘A polyethylene glycol (PEG)-supported NADH model as a novel organic reductant was designed and synthesized. The reductions of various α,β-unsaturated ketones by the PEG-supported NADH model were examined,and the results showed that the reductions completely and quickly proceed with no catalyst at ambient temperature. The main advantages of this liquid-like PEG-supported NADH model are easy workup,and an optimal potential for recycling use and solvent-free for use in reactions.
文摘The rate constant and kinetic isotopic effect(k H/k D) of the reduction of 2-bromo-1-phenylethylidenemalononitrile with NADH model were determined through NMR spectroscopy. The results were consistent with that the hydride transfer step of the reaction which was the rate-determining step, and were comparable to the results obtained through UV-Vis Spectroscopy reported previously.
