A new rhodium catalyzed ring opening reaction of oxabenzonorbornadienes and its derivatives was described. This reaction forms a new carbon-nitrogen bond via an intermolecular allylic displacement of the bridgehead o...A new rhodium catalyzed ring opening reaction of oxabenzonorbornadienes and its derivatives was described. This reaction forms a new carbon-nitrogen bond via an intermolecular allylic displacement of the bridgehead oxygen with a piperazine's derivatives, which proceeds with very high regioselectivity.展开更多
When zero-valent iron(ZVI)is prepared and applied under neutral conditions,it is easy to form oxides or hydroxides on its surface,which hinders the electron release of ZVI.To this end,a nucleophile was introduced into...When zero-valent iron(ZVI)is prepared and applied under neutral conditions,it is easy to form oxides or hydroxides on its surface,which hinders the electron release of ZVI.To this end,a nucleophile was introduced into the ZVI system to inhibit the precipitation of iron ions,improve the conductivity of the solution,and promote the removal efficiency of electrophilic functional groups in organic compounds.In this study,the addition of nucleophiles such as ethylenediamine,methylamine and dimethylamine to the ZVI/H_(2)O_(2)system resulted in an enhanced removal efficiency of tetracycline(TC)under neutral condition,while electrophiles such as EDTA-2Na and oxalic acid dihydrate impeded the removal of TC.Experimental results demonstrated that the presence of nucleophiles could effectively promote the release of iron ions and increase the proportion of ferrous in both aqueous solution and solid surface of ZVI.Experimental and theoretical calculation results revealed that the electrophilic functional group was eliminated in the TC molecule,and the toxicity of the treated solution was reduced significantly.Overall,this work provides a selection of the conditions and pollutants applicable to ZVI under neutral pH conditions.展开更多
A rhodium-catalyzed ring opening reaction of N-Boc-azabenzonorbornadiene with heteroatom nucleophiles was described. Piperidine and piperazine＇s derivatives were nucleophiles in this reaction. The yields of the produ...A rhodium-catalyzed ring opening reaction of N-Boc-azabenzonorbornadiene with heteroatom nucleophiles was described. Piperidine and piperazine＇s derivatives were nucleophiles in this reaction. The yields of the products 2a-f are good and the regioselectivity are excellent.展开更多
The asymmetric desymmetrization of cyclic anhydrides via the addition of carbon-based nucleophiles has been the focus of considerable levels of interest because it leads to optically active products. Over the past 20 ...The asymmetric desymmetrization of cyclic anhydrides via the addition of carbon-based nucleophiles has been the focus of considerable levels of interest because it leads to optically active products. Over the past 20 years, a variety of different catalytic asymmetric alkylation reactions have been developed for the desymmetrization of cyclic anhydrides using different metal reagents as nucleophiles and using chiral ligands. The purpose of this review is to provide an overview of significant developments in this field. ~ 2013 Fen-Er Chen. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
The chemical behaviours of 3-[1'-chloro-3'-(2'-phenyl-1',3'-oxazol-5'-one-4'-ylidene)-propen-1'-yl]coumarin towards nucleophilic reagents (such as hydrolysis,aminolysis,hydroxyl-aminoly...The chemical behaviours of 3-[1'-chloro-3'-(2'-phenyl-1',3'-oxazol-5'-one-4'-ylidene)-propen-1'-yl]coumarin towards nucleophilic reagents (such as hydrolysis,aminolysis,hydroxyl-aminolysis,methanolysis and hydrazinolysis) were described.展开更多
Halogenated aluminates AlCl3, applied as efficient chlorination reagent for hydroxyl groups of substitution alcohols is described. Primary and secondary benzylic alcohols could be transformed into corresponding aromat...Halogenated aluminates AlCl3, applied as efficient chlorination reagent for hydroxyl groups of substitution alcohols is described. Primary and secondary benzylic alcohols could be transformed into corresponding aromatic halides with almost complete conversion and unique selectivity. As chlorination reagent, AlCl3 has an incomparable advantage over others, such as low material cost, commercial availability as well as convenient product isolation.展开更多
文摘A new rhodium catalyzed ring opening reaction of oxabenzonorbornadienes and its derivatives was described. This reaction forms a new carbon-nitrogen bond via an intermolecular allylic displacement of the bridgehead oxygen with a piperazine's derivatives, which proceeds with very high regioselectivity.
基金financial support from Sichuan Science and Technology Program(No.2023NSFSC0345)the Fundamental Research Funds for the Central Universities(Southwest Minzu University,No.ZYN2022002)+1 种基金the Innovation Scientific Research Program for Graduates of Southwest Minzu University(Southwest Minzu University,No.3300222156)the China Scholarship Council(No.202008510077)。
文摘When zero-valent iron(ZVI)is prepared and applied under neutral conditions,it is easy to form oxides or hydroxides on its surface,which hinders the electron release of ZVI.To this end,a nucleophile was introduced into the ZVI system to inhibit the precipitation of iron ions,improve the conductivity of the solution,and promote the removal efficiency of electrophilic functional groups in organic compounds.In this study,the addition of nucleophiles such as ethylenediamine,methylamine and dimethylamine to the ZVI/H_(2)O_(2)system resulted in an enhanced removal efficiency of tetracycline(TC)under neutral condition,while electrophiles such as EDTA-2Na and oxalic acid dihydrate impeded the removal of TC.Experimental results demonstrated that the presence of nucleophiles could effectively promote the release of iron ions and increase the proportion of ferrous in both aqueous solution and solid surface of ZVI.Experimental and theoretical calculation results revealed that the electrophilic functional group was eliminated in the TC molecule,and the toxicity of the treated solution was reduced significantly.Overall,this work provides a selection of the conditions and pollutants applicable to ZVI under neutral pH conditions.
文摘A rhodium-catalyzed ring opening reaction of N-Boc-azabenzonorbornadiene with heteroatom nucleophiles was described. Piperidine and piperazine＇s derivatives were nucleophiles in this reaction. The yields of the products 2a-f are good and the regioselectivity are excellent.
文摘The asymmetric desymmetrization of cyclic anhydrides via the addition of carbon-based nucleophiles has been the focus of considerable levels of interest because it leads to optically active products. Over the past 20 years, a variety of different catalytic asymmetric alkylation reactions have been developed for the desymmetrization of cyclic anhydrides using different metal reagents as nucleophiles and using chiral ligands. The purpose of this review is to provide an overview of significant developments in this field. ~ 2013 Fen-Er Chen. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘The chemical behaviours of 3-[1'-chloro-3'-(2'-phenyl-1',3'-oxazol-5'-one-4'-ylidene)-propen-1'-yl]coumarin towards nucleophilic reagents (such as hydrolysis,aminolysis,hydroxyl-aminolysis,methanolysis and hydrazinolysis) were described.
文摘Halogenated aluminates AlCl3, applied as efficient chlorination reagent for hydroxyl groups of substitution alcohols is described. Primary and secondary benzylic alcohols could be transformed into corresponding aromatic halides with almost complete conversion and unique selectivity. As chlorination reagent, AlCl3 has an incomparable advantage over others, such as low material cost, commercial availability as well as convenient product isolation.
基金Project supported by the National Natural Science Foundation of China(Nos.21672084,21372090)the Special Fund Project of Department of Natural Resources of Guangdong Province(Guangdong Natural Resources Cooperation)(No.2020037)。
