Synthesis method of chromium 2-pyridylformate

Abstract

The invention discloses a synthesis method of chromium 2-pyridylformate, which comprises the following steps: by using 2-methylpyridine, potassium permanganate and chromium chloride alcoholic solution as raw materials, adding a phase-transfer catalyst to synthesize the chromium 2-pyridylformate, wherein the phase-transfer catalyst is a quaternary ammonium salt or quaternary phosphonium salt in onium salt phase-transfer catalysts, preferably ammonium tetrabutylbromide, ammonium tetrabutylchloride or phosphonium methyltriphenylbromide. The method disclosed by the invention uses the phase-transfer catalyst to enable the sufficient reaction of 2-methylpyridine in an inorganic reaction environment, thereby enhancing the reaction yield (up to higher than 71%); the methanol or ethanol is used as the solvent to enhance the yield of the reaction step; and the solvent is recyclable, thereby saving the raw material cost, promoting the effective performance of the complex reaction, enabling the product to precipitate sufficiently, enhancing the maximum product yield by nearly 40%, and ensuring the yield and quality of the product.

Description

Technical field

[0001] The invention relates to a method for synthesizing chromium 2-picolinate. Background technique

[0002] Chromium 2-picolinate, also known as chromium 2-picolinate, its English name is chromium picolinate, and its structural formula is as follows:

[0003]

[0004] The molecular formula is C 18 H 12 N 3 O 6 Cr is a purple-red crystalline fine powder, stable at room temperature, slightly soluble in water, insoluble in ethanol, and chromium is trivalent chromium.

[0005] In the periodic table of elements, chromium belongs to the VIB group of the first transition system. It is a silver-white metal with an atomic weight of 51.996 and an atomic number of 24. It is hard and brittle. Its more common oxidation state is 0, + 2, + 3 and + 6. With the increase of valence, the oxidability increases. Divalent chromium is unstable in the air and can be oxidized into trivalent chromium. Hexavalent chromium is mainly combined with oxygen to form chromate and dichromate. It is...

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