Imperial Chemical Industries Limited

Roy Dennis Bowden

Thomas Seaton

Leslie Burgess

Raymond J Clark

A method for the preparation of a fluorinated amine of the formula: ##STR1## wherein X represents hydrogen or fluorine, R represents hydrogen, lower alkyl, difluoromethyl or trifluoromethyl and each of R.sup.1 and R.sup.2, independently, represents hydrogen or lower alkyl, which comprises reacting a carbonyl compound of the formula:

Chemical process

4,4'-difluoro-benzophenone is prepared from 4,4'-diamino-diphenylmethane by diazotization in anhydrous or concentrated aqueous hydrogen fluoride and decomposition of the diazonium fluoride thus produced in the presence of nitrous acid or nitrite as oxidizing agent.

Preparation of aromatic fluoro-compounds

Partially-chlorinated derivatives of 3-methylpyridine, containing a single chlorine atom as substituent in the pyridine ring and either two or three chlorine atoms as substituents in the methyl group, are prepared by vapor-phase chlorination of 3-methylpyridine.

Chlorination process

2,3,5-Trichloropyridine is prepared by the vapor phase chlorination of 3,5-dichloropyridine.

Chlorination process for producing 2,3,5-trichloropyridine

The present invention deals with intermediate compounds, namely 4-(2'-, 3'- and 4'-pyridyl)-tetrahydropyrans and a process for their preparation. These compounds are prepared by reacting a 2'-haloethyl-3-(pyridyl)propyl ether with an alkali metal amide at -80.degree. C. to 40.degree. C.

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Runcorn, United Kingdom

Roy Dennis Bowden