METHOD OF ELECTROCHEMICAL DECHLORINATION OF POLYCHLORINEPYRIDINE CARBOXYLIC ACIDS Russian patent published in 1994 - IPC

FIELD: organic chemistry. SUBSTANCE: method involves electrochemical reduction of polychlorinepyridine carboxylic acid at normal temperature within 10 h. The process takes place in aqueous- alkali medium on Ag-Zn-Cu cathode; potential difference being 1.7- 207 V, current density being 250-20 A/m². The process is followed by neutralization of reaction mass with the help of concentrated HCl, by extraction and by crystallization of desired product. Above mentioned cathode contains, mass % : Ag 20-70, Zn 10-40, Cu up to 100. Thus mono-, di- and trichlorinepyridine carboxylic acids are prepared, their yield being 82-93% . EFFECT: simplifies the process, decreases expense of silver. 4 tbl