Lonza Inc.

David L Kuo

Jean-Paul Roduit

Alain Wellig

Martin Eyer

Robert Voeffray

The present invention relates to process of halogenating an alkynol having 3 to 20 carbon atoms to produce a compound having the formula: R-C.tbd.(C--CH.sub.2).sbsb.x-OH, wherein R is F, Cl, Br or I and x is 1 to 18. In particular, this invention provides a process for preparing a halopropynyl alcohol, specifically iodopropynyl alcohol. In one embodiment, iodopropynyl alcohol is produced by sequentially adding potassium hydroxide, potassium iodide and an oxidizing agent to a solution of propynyl alcohol at a rate and temperature sufficient to produce an iodopropynyl alcohol.

Synthesis of haloalkynol

A process for preparing imidazopyridine derivatives of the general formula: ##STR1## wherein R.sub.1 is hydrogen or an alkyl group, and R.sub.2, R.sub.3 and R.sub.4 are identical or different and are hydrogen, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or a halogen atom. In this process, a 2-amino-3-nitropyridine is hydrogenated in the presence of a hydrogenation catalyst and the hydrogenation product is condensed with a carboxylic acid simultaneously present in the reaction mixture to give the end product. The imidazopyridine derivatives are intermediates for the preparation of angiotensin II antagonists.

Process for preparing imidazopyridine derivatives

Process for the production of 2,3-dichloro-5-acetylpyridine by reaction of a 5,6-dichloronicotinic acid halide with a methyl magnesium halide in an inert organic diluent. The reaction is performed in the presence of a Cu/Cu halide as the catalyst.

Process for the production of 2,3-dichloro-5-acetylpyridine

A process for the production of piperazinylpyrimidine derivatives of the formula: ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are the same or different and each is a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, branched or unbranched. These piperazinylpyrimidine derivatives are acid-converted with cyanamide to an amidine salt starting from piperazine or its hydrate and then reacted with a dicarbonyl compound in the presence of a base to the end product.

Process for the production of piperazinylpyrimidine derivatives

A process for the production of piperazinylpyrimidine derivatives of the formula I: ##STR1## wherein R.sub.1 is a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, branched or unbranched. In the process, piperazine or its hydrate is acid-converted with cyanamide to an amidine salt and the latter is then reacted with a carbonyl compound in the presence of a base to the end product.

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Brig, Switzerland

David L Kuo