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Large-scale solvent-free chlorination of hydroxy-pyrimidines, -pyridines, -pyrazines and -amides using equimolar POCl?.

ABSTRACT: Chlorination with equimolar POCl? can be efficiently achieved not only for hydroxypyrimidines, but also for many other substrates such as 2-hydroxy-pyridines, -quinoxalines, or even -amides. The procedure is solvent-free and involves heating in a sealed reactor at high temperatures using one equivalent of pyridine as base. It is suitable for large scale (multigram) batch preparations.

SUBMITTER: Wang H

PROVIDER: S-EPMC6290571 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Large-scale solvent-free chlorination of hydroxy-pyrimidines, -pyridines, -pyrazines and -amides using equimolar POCl₃.

Wang Han H Wen Kun K Wang Le L Xiang Ye Y Xu Xiaocheng X Shen Yongjia Y Sun Zhihua Z

Molecules (Basel, Switzerland) 20120416 4

Chlorination with equimolar POCl₃ can be efficiently achieved not only for hydroxypyrimidines, but also for many other substrates such as 2-hydroxy-pyridines, -quinoxalines, or even -amides. The procedure is solvent-free and involves heating in a sealed reactor at high temperatures using one equivalent of pyridine as base. It is suitable for large scale (multigram) batch preparations. ...[more]

PMID: 22508333

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