| 摘要 |
Process for preparing terpyridines of the formula I in which R are hydrogens or identical C1-C12-alkyl or C1-C12-alkoxy radicals and n is 0, 1, 2, 3 or 4 and is the same for both sets of radicals R, comprises the successive reaction steps: A') acid hydrolysis of a 2-cyanopyridine derivative by means of an anhydrous inorganic acid or its anhydride in the presence of water and a C1-C4-alkanol, with an equimolar amount of water being added to the 2-cyanopyridine derivative prior to addition of the anhydrous inorganic acid or its anhydride, A) condensation of the C1-C4-alkyl pyridine-2-carboxylate derivative obtained in reaction step A' with acetone in an aprotic solvent in the presence of an alkali metal C1-C4-alkoxide or alkaline earth metal C1-C4-alkoxide as base, B) reaction of the 1,5-bis(2-pyridyl)pentane-1,3,5-trione derivative obtained in reaction step A with ammonia or ammonium salts (NH4)qY with removal of the water of reaction formed using a C1-C4-alkanol as entrainer, where the variable Y in (NH4)qY is the 40 anion of the parent q-basic acid HqY of the ammonium salt, and C) chlorination of the 2,6-bis(2-pyridyl)-4(1H)pyridinone derivative obtained in reaction step B using phosphorus oxide chloride (POCl3) or using a mixture comprising phosphorus oxide chloride and at least one organic solvent selected from the group consisting of toluene, o-xylene, m-xylene and p-xylene. Also provided are a process for preparing C1-C4-alkyl pyridine-2-carboxylate derivatives from 2-cyanopyridine derivatives, a process for preparing 1,5-bis(2-pyridyl)pentane-1,3,5-trione derivatives by condensation of a C1-C4-alkyl pyridine-2-carboxylate derivative with acetone, a process for preparing 2,6-bis(2-pyridyl)-4(1H)pyridinone derivatives by reaction of a 1,5-bis(2-pyridyl)pentane-1,3,5-trione derivative with ammonia or ammonium salts and a process for preparing terpyridines of the formula I by chlorination of a 2,6-bis(2-pyridyl)-4(1H)pyridinone derivative.
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