Abstract

Heating of 2-halopyridine-3,4-dicarboxylic acids in propionic anhydride led to the formation of 4-halofuro[3,4-c]pyridine-1,3-diones as a result of intramolecular dehydration of the vicinal carboxy groups. The subsequent reduction of 4-halofuro[3,4-c]pyridine-1,3-diones with sodium tetrahydridoborate in THF at room temperature afforded 4-halofuro[3,4-c]pyridin-3(1H)-ones as the major products.

中文翻译：

---

从2-卤代吡啶-3,4-二甲腈合成4-卤代呋喃并[3,4-c]吡啶-3（1 H）-一

摘要

由于邻位羧基的分子内脱水，在丙酸酐中加热2-卤代吡啶-3,4-二羧酸导致4-卤代呋喃并[3,4- c ]吡啶-1,3-二酮的形成。随后在室温下用四氢硼酸钠在THF中还原4-卤代呋喃并[3,4- c ]吡啶-1,3-二酮，得到4-卤代呋喃并[3,4- c ]吡啶-3（1 H）-主要产品。