A highly efficient and selective N-alkylation reaction of 2-amino-4H-chromene-3-carbonitrile derivatives using various alcohols as alkylation agent were developed in the presence of AlCl3 as a catalyst as well as CH3C...A highly efficient and selective N-alkylation reaction of 2-amino-4H-chromene-3-carbonitrile derivatives using various alcohols as alkylation agent were developed in the presence of AlCl3 as a catalyst as well as CH3COOH as an additive,in which the cyano group kept inert and the amino group was alkylated in high yields.All the target products were characterized and determined by infrared(IR),1H NMR,13C NMR,and HRMS.And the X-ray structure of product 3ab was obtained.A bimolecular reaction mechanism catalyzed by AlCl3 was proposed under the assistance of CH3COOH.展开更多
Polycarbonate diols（PCDLs） with a number average molecular weight（M,） of 2800 and a narrow polydispersity index（PDI=1.33） were synthesized from dimethyl carbonate（DMC） and 1,4-butarlediol（BD） via a two-step ...Polycarbonate diols（PCDLs） with a number average molecular weight（M,） of 2800 and a narrow polydispersity index（PDI=1.33） were synthesized from dimethyl carbonate（DMC） and 1,4-butarlediol（BD） via a two-step process. The influences of the molar ratios of DMC to BD in the feedstock, polycondensation temperature and polycondensation time on the PCDLs preparation were studied. CH3COONa showed the best catalytic performance among the catalysts studied. The highest BD conversion of 73.8% and PCDLs yield of 64.7% were achieved under its optimum reaction conditions. Furthennore, based on the results of 1^H NMR, the relationships between the ratio of end groups （--OCH3/-OH） of oligomers, the Mn and chain-end constitute of resultant polycarbonates were also investigated. The results indicate that PCDLs can be synthesized when the oligomers mostly bear hydroxyl end groups. In contrast, it was impossible to prepare PCDLs when the oligomers were enriched with methyl carbonate end groups,展开更多
基金Supported by the National Natural Science Foundation of China(Nos.21506106,21978410)the Natural Science Foundation of Heilongjiang Province,China(No.LC2017004)+2 种基金the Echelon Reserve Leader Fund for the Leading Talent of Heilongjiang Province,Chinathe Fundamental Research Project for Universities in Heilongjiang Province,China(Nos.135209209,135209220,LTSW201735,YSTSXK201853,YSTSXK201859)the Graduate Innovation Foundation of Qiqihar University,China(NO.YJSCX2018-ZD18).
文摘A highly efficient and selective N-alkylation reaction of 2-amino-4H-chromene-3-carbonitrile derivatives using various alcohols as alkylation agent were developed in the presence of AlCl3 as a catalyst as well as CH3COOH as an additive,in which the cyano group kept inert and the amino group was alkylated in high yields.All the target products were characterized and determined by infrared(IR),1H NMR,13C NMR,and HRMS.And the X-ray structure of product 3ab was obtained.A bimolecular reaction mechanism catalyzed by AlCl3 was proposed under the assistance of CH3COOH.
文摘Polycarbonate diols（PCDLs） with a number average molecular weight（M,） of 2800 and a narrow polydispersity index（PDI=1.33） were synthesized from dimethyl carbonate（DMC） and 1,4-butarlediol（BD） via a two-step process. The influences of the molar ratios of DMC to BD in the feedstock, polycondensation temperature and polycondensation time on the PCDLs preparation were studied. CH3COONa showed the best catalytic performance among the catalysts studied. The highest BD conversion of 73.8% and PCDLs yield of 64.7% were achieved under its optimum reaction conditions. Furthennore, based on the results of 1^H NMR, the relationships between the ratio of end groups （--OCH3/-OH） of oligomers, the Mn and chain-end constitute of resultant polycarbonates were also investigated. The results indicate that PCDLs can be synthesized when the oligomers mostly bear hydroxyl end groups. In contrast, it was impossible to prepare PCDLs when the oligomers were enriched with methyl carbonate end groups,
