Understanding the Alkylation of a Phenol by 1-(3-Chloropropyl)pyrrolidine: Evidence for the Intermediacy of an Azetidinium Ion
作者:Ian W. Ashworth、Lai C. Chan、Brian G. Cox、Ian M. McFarlane、Andrew R. Phillips
DOI:10.1021/acs.joc.8b02458
日期:2019.4.19
The final synthetic step in the synthesis of cediranib, AZD2171, 1, is the alkylation of a phenol with an alkyl halide to generate an ether. Our need to understand and control the formation of synthetic impurities generated in this step of the synthesis led us to investigate the kinetics and mechanism of the alkylation of indolphenol, 2, 4-[(4-fluoro-2-methyl-1H-indol-5-yl)oxy]-6-methoxyquinazolin-7-ol
在西地尼布,AZD2171,的合成中的最终的合成步骤1,是与烷基卤,以生成醚酚的烷基化。我们需要了解和控制的,在合成的此步骤中生成的合成杂质的形成导致我们调查indolphenol,的烷基化的动力学和机制2,4 - [(4-氟-2-甲基-1- ħ -吲哚-5-基)氧基] -6-甲氧基-7-醇,由chloropyrrolidine,3,1-(3-氯丙基)吡咯烷。在1-甲基-2-吡咯烷酮的研究(NMP)建立的活性烷基化剂是氮杂环丁鎓离子,4,4-氮鎓螺[3.4]辛烷,经由chloropyrrolidine,缓慢分子内环化反应而形成的3。通过在四苯基硼酸钾水溶液的存在下加热3,从水中分离出氮杂环丁烷鎓离子作为其四苯基硼酸盐,并且通过与2快速反应生成西地尼布1证明了其作为中间体的能力。