Cyclic utilization method of production mother liquor of 4-ethyl-2, 3-dioxopiperazine-1-formyl chloride

Abstract

The invention discloses a cyclic utilization method of production mother liquor in a production method of 4-ethyl-2, 3-dioxopiperazine-1-formyl chloride in CN10147982A. The method comprises the stepsof: carrying out heating reflux treatment on production mother liquor to decompose a small amount of residual bis (trichloromethyl) carbonate, carrying out distillation separation treatment to obtaina distillate and a residual solution, recycling the distillate in the production process of 4-ethyl-2, 3-dioxopiperazine-1-formyl chloride, and recycling the residual solution in the crystallization process of 4-ethyl-2, 3-dioxopiperazine-1-formyl chloride. According to the cyclic utilization method, high-added-value comprehensive utilization of all effective components in the production mother liquor is achieved, production and product performance of 4-ethyl-2, 3-dioxopiperazine-1-formyl chloride cannot be affected, the yield of the target product can be increased to 88.0% or above, and the purity can reach 97.0% or above.

Description

technical field [0001] The present invention relates to the production technology of pharmaceutical intermediate 4-ethyl-2,3-dioxopiperazine-1-formyl chloride, in particular to a kind of 4-ethyl-2,3-dioxypiperazine-1-formyl chloride A method for recycling the production mother liquor produced in the production of acid chlorides. Background technique [0002] CN 101417982A discloses a synthesis and crystallization method of 4-ethyl-2,3-dioxypiperazine-1-formyl chloride, which uses 4-ethyl-2,3-dioxypiperazine as a starting material, Trimethylchlorosilane ((CH 3 ) 3 SiCl) is the activator and protective agent, triethylamine is the acid-binding agent and catalyst, reacts with the formyl chloride reagent bis(trichloromethyl)carbonate (BTC) in the reaction solvent, and filters out the insoluble triethylamine salt , adding a crystallization agent to obtain crystallization of the target product 4-ethyl-2,3-dioxypiperazine-1-formyl chloride. The specific reaction equation is as f...

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Problems solved by technology

[0007] Although the above-mentioned traditional treatment process for producing mother liquor is relatively simple and mature, there are mainly three deficiencies in the following aspects: 1) The residual trimethylchlorosilane and target products in the production mother liquor are directly hydrolyzed and destroyed, and cannot be processed with high added value. Utilization; 2) After the production mother liquor is destroyed by adding alkaline water, it not only needs to consume a large amount of alkali liquor, but also produces a large amount (about 0.95-1.02kg / kg of production mother liquor) of high-salt and high-COD wastewater, and the NaCl content in the wastewater is 6.1 ~7.5%, COD value 180000~210000mg / L, the follow-up harmless treatment of these waste water is very difficult and costly; rate of 82 to 85%), crystallization agent (recovery rate of 70 to 75%), and the hydrolysis product of trimethylchlorosilane hexamethyldisiloxane (yield of 70 to 78%) are relatively large losses, but also Produce 1~1.5% viscous still residue, which must be incinerated by entrusting a qualified unit at a high price

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