A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylat...A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylation of p-amino diphenylamine （PADPA） and methylisobutyl ketone （MIBK） to afford N-（1,3-dimethylbutyl）-N^-phenyl-p-phenylenedianine （DBPPD） with conversion up to 99.42% and selectivity to 97.46%. Comparing with the other common palladium sulfide catalysts, the membrane of palladium sulfide on the surface and the core of palladium metal cause the Pd on the surface of the new catalyst in a lower sulfur coordination, which improves its activity. Our result indicates that this new egg-shell Pd-S/C is an efficient hydrogenation catalyst.展开更多
A flexible approach to ethyl (3R,4S)-N-Boc-4-amino-3-hy-droxy-5-phenyIpentanoate (N-Boc-AHPPA-OEt), the γ-amino-β-hydroxy add moiety of hapalosin is described. The synthetic method features a ring-opening ethanolysi...A flexible approach to ethyl (3R,4S)-N-Boc-4-amino-3-hy-droxy-5-phenyIpentanoate (N-Boc-AHPPA-OEt), the γ-amino-β-hydroxy add moiety of hapalosin is described. The synthetic method features a ring-opening ethanolysis of an activated N-Boc-lactam, which is obtained via a diastereoselective reductive-alkylation of (R)-malimide derivative. The flexibility of the method resides hi the introduction of the alkyl side chain by Grignard reagent addition.展开更多
基金supported by Zhejiang Provincial Natural Science Foundation of China(No LY12B03009)Program from Science and Technology Department of Zhejiang Province(No2011R09020-03)
文摘A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylation of p-amino diphenylamine （PADPA） and methylisobutyl ketone （MIBK） to afford N-（1,3-dimethylbutyl）-N^-phenyl-p-phenylenedianine （DBPPD） with conversion up to 99.42% and selectivity to 97.46%. Comparing with the other common palladium sulfide catalysts, the membrane of palladium sulfide on the surface and the core of palladium metal cause the Pd on the surface of the new catalyst in a lower sulfur coordination, which improves its activity. Our result indicates that this new egg-shell Pd-S/C is an efficient hydrogenation catalyst.
基金Project supported by the National Science Foundation for Distinguished Young Investigators,the National Natural Science Foundation of China and the Fund for doctoral sites of the Ministry of Education.
文摘A flexible approach to ethyl (3R,4S)-N-Boc-4-amino-3-hy-droxy-5-phenyIpentanoate (N-Boc-AHPPA-OEt), the γ-amino-β-hydroxy add moiety of hapalosin is described. The synthetic method features a ring-opening ethanolysis of an activated N-Boc-lactam, which is obtained via a diastereoselective reductive-alkylation of (R)-malimide derivative. The flexibility of the method resides hi the introduction of the alkyl side chain by Grignard reagent addition.
