Boron nitride containing hydroxyl groups efficiently catalysed oxidative dehydrogenation of ethane to ethylene,offering rather high selectivity（95%） but only small amount of CO2 formation（0.4%） at a given ethane c...Boron nitride containing hydroxyl groups efficiently catalysed oxidative dehydrogenation of ethane to ethylene,offering rather high selectivity（95%） but only small amount of CO2 formation（0.4%） at a given ethane conversion of 11%.Even at high conversion level of 63%,the selectivity of ethylene retained at 80%,which is competitive with the energy-demanding industrialized steam cracking route.A long-term test for 200 h resulted in stable conversion and product selectivity,showing the excellent catalytic stability.Both experimental and computational studies have identified that the hydrogen abstraction of B-OH groups by molecular oxygen dynamically generated the active sites and triggered ethane dehydrogenation.展开更多
Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.
We report a synthetic design and the experimental exploration of preparation of disubstituted polyacetylenes （PAs, P3） through 1,3-dipolar cycloaddition of azides with precursor PA bearing alkyne pendants. The precu...We report a synthetic design and the experimental exploration of preparation of disubstituted polyacetylenes （PAs, P3） through 1,3-dipolar cycloaddition of azides with precursor PA bearing alkyne pendants. The precursor PA （P2） was derived by desilylation of the pristine PA with trimethylethynylsilane side chains （P1）. P1 was obtained by polymerization of a dual-alkyne containing monomer with one of the alkynes end-capping by trimethylsilane （M） under the promotion of WC16-Ph4Sn catalyst. Two synthetic routes, i.e. two-steps （from P1 to P3 via precursor P2） and one-pot （from P1 to P3 without separation and purification of P2） were tried and the results indicated that one-pot strategy is more facile and resultant P3-1 showed higher purity and higher molecular weight than the resultant of P3-2. By using the techniques such as GPC, FTIR and 1H NMR spectroscopy the polymerization behavior and the structures of the polymers were well characterized.展开更多
基金supported by the National Natural Science Foundation of China (21225312, U1462120, 21473206)Cheung Kong Scholars Programme of China (T2015036)~~
文摘Boron nitride containing hydroxyl groups efficiently catalysed oxidative dehydrogenation of ethane to ethylene,offering rather high selectivity（95%） but only small amount of CO2 formation（0.4%） at a given ethane conversion of 11%.Even at high conversion level of 63%,the selectivity of ethylene retained at 80%,which is competitive with the energy-demanding industrialized steam cracking route.A long-term test for 200 h resulted in stable conversion and product selectivity,showing the excellent catalytic stability.Both experimental and computational studies have identified that the hydrogen abstraction of B-OH groups by molecular oxygen dynamically generated the active sites and triggered ethane dehydrogenation.
基金supported by the US Air Force Office of Scientific Research (F49550-10-1-0521)
文摘Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.
基金partially supported by the National Natural Science Foundation of China (21074113,20634020 & 20974028)the National Basic Research Program of China (973 Program,2009CB623605)+1 种基金the Research Grants Council of Hong Kong (603509 & HKUST2/CRF/10)the University Grants Committee of Hong Kong (AoE/P-03/08)
文摘We report a synthetic design and the experimental exploration of preparation of disubstituted polyacetylenes （PAs, P3） through 1,3-dipolar cycloaddition of azides with precursor PA bearing alkyne pendants. The precursor PA （P2） was derived by desilylation of the pristine PA with trimethylethynylsilane side chains （P1）. P1 was obtained by polymerization of a dual-alkyne containing monomer with one of the alkynes end-capping by trimethylsilane （M） under the promotion of WC16-Ph4Sn catalyst. Two synthetic routes, i.e. two-steps （from P1 to P3 via precursor P2） and one-pot （from P1 to P3 without separation and purification of P2） were tried and the results indicated that one-pot strategy is more facile and resultant P3-1 showed higher purity and higher molecular weight than the resultant of P3-2. By using the techniques such as GPC, FTIR and 1H NMR spectroscopy the polymerization behavior and the structures of the polymers were well characterized.
