Method for recycling methanol in preparation of cefprozil intermediate

Abstract

The invention relates to a method for recycling methanol in the preparation of a cefprozil intermediate. The method comprises the following steps: (1) reacting GCLE used as an initial raw material with sodium iodide and triphenylphosphine to generate intermediate phosphorus onium salt, and carrying out Witing reaction on phosphorus onium salt and acetaldehyde to generate GPRE; (2) after the Witing reaction is finished, carrying out reduced pressure distillation to remove dichloromethane, and then dropwise adding methanol and water to precipitate the GPRE; (3) carrying out suction filtration on a reaction liquid, wherein a filter cake is the GPRE, filter liquor is mother liquor and contains methanol and the water; (4) transferring the mother liquor to an evaporator, and evaporating and recovering methanol (which contains the water); (5) measuring the water ratio of recovered methanol; and (6) adding recovered methanol to the step (2) in proportion to continue a subsequent step. The method disclosed by the invention can be used for mainly solving the problem of recycling of methanol, obtaining preferable yield and product quality, solving the problem of pollution of a large amount of organic waste liquor, reducing the cefprozil production cost and realizing the maximization of economic benefits.

Description

technical field [0001] The invention relates to the technical field of medicine, in particular to a method for recovering methanol in the preparation process of a cefprozil intermediate (GPRE). Background technique [0002] Cefprozil is a semi-synthetic second-generation broad-spectrum cephalosporin against Gram-positive bacteria. The mechanism of action is to inhibit the synthesis of bacterial cell walls, causing the bacteria to rupture and dissolve rapidly. It can be used for mild to moderate skin and respiratory tract infections caused by sensitive bacteria . After oral administration, this product has a high blood concentration, a half-life of about 1.3 hours, a serum protein binding rate of about 45%, and a 24-hour prototype recovery rate of about 70-80% in urine. CFPZ dose up to 1000mg is still well tolerated, showing a linear pharmacokinetic relationship. It is suitable for the treatment of pharyngitis, tonsillitis, acute bronchitis, pneumonia, scarlet fever, acute ...

AI Technical Summary

Problems solved by technology

This route has the advantages of high yield, simple production process, mild production conditions, etc., but there is also the problem of organic wastewater pollution

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