A new debenzylation of benzyl esters by silica-supported sodium hydrogen sulfate is described. The debenzylation could be achieved selectively and efficiently in good to excellent yields without affecting sensitive fu...A new debenzylation of benzyl esters by silica-supported sodium hydrogen sulfate is described. The debenzylation could be achieved selectively and efficiently in good to excellent yields without affecting sensitive functional groups such as nitro, unsaturated bonds, and ethyl ester.展开更多
tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and te...tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and tert-butyl （R）-3-amino-3-phenylpropanoate（7） were generated as the byproducts under the general catalytic hydrogenation Pd（OH）2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.展开更多
CM1, (-)CM1 as well as (±)CM1–the metabolites of clausenamide were synthesized from b-phenyl-(N-p-methoxylbenzyl)-ethanol amine through 8 and 6 steps respec- tively.
substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N?-dibenzyl-1,3-propylene diamine and methyl-2,3-dibromo propionate through nucleophilic substitution, reduction, chlorination and debe...substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N?-dibenzyl-1,3-propylene diamine and methyl-2,3-dibromo propionate through nucleophilic substitution, reduction, chlorination and debenzylation.展开更多
The additive reactivity of 2,6,8,12-tetraacetyl-4, 10-dibenzyl-2,4,6,8,10,12-hexazatetracyclo [5.5.0.05.9. 03.11] dodecane (3) in several conditions was studied. It was found that the N-benzyl groups in compound 3 cou...The additive reactivity of 2,6,8,12-tetraacetyl-4, 10-dibenzyl-2,4,6,8,10,12-hexazatetracyclo [5.5.0.05.9. 03.11] dodecane (3) in several conditions was studied. It was found that the N-benzyl groups in compound 3 could be oxidized to benzoyl groups by Cr(VI) reagents, and could be removed by cerium ammonium nitrate (CAN), meanwhile nitroamine products were given.展开更多
The debenzylation and selective de-tert-butylation of p-tert-calix[4]arene derivatives were studied and 11, 17, 23-tri-tert-butyl-25, 26, 27-tri-O-etherated calix[4] arenes were synthesized by a simultaneous debenzyla...The debenzylation and selective de-tert-butylation of p-tert-calix[4]arene derivatives were studied and 11, 17, 23-tri-tert-butyl-25, 26, 27-tri-O-etherated calix[4] arenes were synthesized by a simultaneous debenzylation and selective de-tert-butylation process.展开更多
基金support from National Science Foundation of China(Nos.03772648 and 30721005)Knowledge Innovation Program of the Chinese Academy of Sciences(No.06G8031014)
文摘A new debenzylation of benzyl esters by silica-supported sodium hydrogen sulfate is described. The debenzylation could be achieved selectively and efficiently in good to excellent yields without affecting sensitive functional groups such as nitro, unsaturated bonds, and ethyl ester.
基金Supported by the National Key New Drug Creation Program of China(No.2009ZX09103-001)the Jiangsu Key Laboratory of Molecular Targeted Antitumor Drug Research Foundation China(No.BM2008201)
文摘tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and tert-butyl （R）-3-amino-3-phenylpropanoate（7） were generated as the byproducts under the general catalytic hydrogenation Pd（OH）2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.
基金This work was supporcd by the National Natural Science Foundation of China(No.29790121)
文摘CM1, (-)CM1 as well as (±)CM1–the metabolites of clausenamide were synthesized from b-phenyl-(N-p-methoxylbenzyl)-ethanol amine through 8 and 6 steps respec- tively.
基金the Shanghai Development Fund of Science and Technology.
文摘substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N?-dibenzyl-1,3-propylene diamine and methyl-2,3-dibromo propionate through nucleophilic substitution, reduction, chlorination and debenzylation.
文摘The additive reactivity of 2,6,8,12-tetraacetyl-4, 10-dibenzyl-2,4,6,8,10,12-hexazatetracyclo [5.5.0.05.9. 03.11] dodecane (3) in several conditions was studied. It was found that the N-benzyl groups in compound 3 could be oxidized to benzoyl groups by Cr(VI) reagents, and could be removed by cerium ammonium nitrate (CAN), meanwhile nitroamine products were given.
基金Project supported by the National Natural Science Foundation of China (No. 29872041) and the Analytical Centre of Nanjing University.
文摘The debenzylation and selective de-tert-butylation of p-tert-calix[4]arene derivatives were studied and 11, 17, 23-tri-tert-butyl-25, 26, 27-tri-O-etherated calix[4] arenes were synthesized by a simultaneous debenzylation and selective de-tert-butylation process.
