Patents Assigned to ZHEJIANG XIANFENG TECHNOLOGIES CO., LTD.
  • Publication number: 20200048206
    Abstract: A method for preparing 5-(4-bromophenyl)-4,6-dichloropyrimidine is provided. The method comprises the steps of: preparing methyl p-bromophenylacetate (Intermediate I) by catalytic esterification of p-bromophenylacetic acid, and then reacting with dimethyl carbonate to synthesize 2-(4-bromophenyl)-malonic acid-1,3-dimethyl ester (Intermediate 2), cyclizing with formamidine hydrochloride to obtain 5-(4-bromophenyl)-4,6-dihydroxypyrimidine (Intermediate 3), and then chlorinating to give the product 5-(4-bromophenyl)-4,6-dichloropyrimidine. In the process of preparing Intermediate 1 in the present invention, a solid acid is used as a catalyst. Moreover, in the process of preparing Intermediate 2, sodium methoxide is used as a base in place of sodium hydride or sodium amide used in the prior art. Furthermore, Intermediate 3 is prepared by a one-pot process.
    Type: Application
    Filed: January 9, 2019
    Publication date: February 13, 2020
    Applicant: ZHEJIANG XIANFENG TECHNOLOGIES CO.,LTD
    Inventors: Feifei GAO, Junlong GAO, Minliang ZHU, Wei LU, Yi LIU
  • Patent number: 10556871
    Abstract: A method for preparing 5-(4-bromophenyl)-4,6-dichloropyrimidine is provided. The method comprises the steps of: preparing methyl p-bromophenylacetate (Intermediate I) by catalytic esterification of p-bromophenylacetic acid, and then reacting with dimethyl carbonate to synthesize 2-(4-bromophenyl)-malonic acid-1,3-dimethyl ester (Intermediate 2), cyclizing with formamidine hydrochloride to obtain 5-(4-bromophenyl)-4,6-dihydroxypyrimidine (Intermediate 3), and then chlorinating to give the product 5-(4-bromophenyl)-4,6-dichloropyrimidine. In the process of preparing Intermediate 1 in the present invention, a solid acid is used as a catalyst. Moreover, in the process of preparing Intermediate 2, sodium methoxide is used as a base in place of sodium hydride or sodium amide used in the prior art. Furthermore, Intermediate 3 is prepared by a one-pot process.
    Type: Grant
    Filed: January 9, 2019
    Date of Patent: February 11, 2020
    Assignee: ZHEJIANG XIANFENG TECHNOLOGIES CO., LTD.
    Inventors: Feifei Gao, Junlong Gao, Minliang Zhu, Wei Lu, Yi Liu