Synthesis of α-alkylidene-γ-butyrolactones<i>via</i>Ring-cleavage/recyclization of 2-Amino-4,5-dihydro-3-furancarboxamides
作者:Fumi Okabe、Yoshinobu Tagawa、Kenji Yamagata
DOI:10.1002/jhet.5570410405
日期:2004.7
The reactions of 2-amino-4,5-dihydro-3-furancarboxarnides 1a,b with cyanomethylene compounds (such as alkyl cyanoacetates and malononitrile) gave the corresponding ring-opened products 2a-f. Compounds 2a-d reacted with methanesulfonic acid to give the corresponding α-alkylidene-γ-butyrolactones 3a-d. On the other hand, treatment of 2e,f with methanesulfonic acid yielded 3-pyridinecarbonitrile derivatives
2-氨基-4,5-二氢-3-呋喃甲酰胺1a,b与氰基亚甲基化合物(例如氰基乙酸烷基酯和丙二腈)反应,得到相应的开环产物2a-f。化合物2a-d与甲磺酸反应,得到相应的α-亚烷基-γ-丁内酯3a-d。另一方面,用甲磺酸处理2e,f得到3-吡啶甲腈衍生物4a,b。