A Convenient Synthesis of (<i>E</i>)-4-Alkoxy-2-amino-3-butenoic Acid Derivatives
作者:Kazuhiro Kobayashi、Susumu Irisawa、Hideki Akamatsu、Masaki Takahashi、Taichi Kitamura、Miyuki Tanmatsu、Osamu Morikawa、Hisatoshi Konishi
DOI:10.1246/bcsj.72.2307
日期:1999.10
(E)-4-Alkoxy-2-formylamino-3-butenoic acid esters have been prepared in two steps from 3-alkoxy-1-isocyanopropenes. The method is based on the reaction of 3-alkoxy-1-isocyano-1-lithiopropenes, which can be generated by the treatment of 3-alkoxy-1-isocyanopropenes with LDA in THF at −78 °C, with alkyl chlorocarbonates, affording 4-alkoxy-2-isocyano-3-butenoates. These isocyano esters have been easily
(E)-4-烷氧基-2-甲酰氨基-3-丁烯酸酯已由 3-烷氧基-1-异氰基丙烯分两步制备。该方法基于 3-alkoxy-1-isocyano-1-lithiopropenes 的反应,3-alkoxy-1-isocyano-1-lithiopropenes 可以通过在 -78 °C 的 THF 中用 LDA 处理 3-alkoxy-1-isocyanopropenes 与氯代碳酸烷基酯的反应,得到4-烷氧基-2-异氰基-3-丁烯酸酯。通过在-20 °C 的 Et2O 中用浓 HCl 处理,这些异氰酯很容易转化为相应的甲酰氨基酯。随后,通过用氯碳酸乙酯进行乙氧基羰基化,然后使用六甲基磷酰三胺 (HMPA) 作为共溶剂,用烷基卤化物进行烷基化,将取代基引入 2-位。