A kind of production method of m-aminoacetanilide

Abstract

The invention discloses a production method of m-aminoacetanilide, which comprises the following steps: step 1: put m-aminoacetanilide hydrochloride in a proportion into a reaction kettle, apply mother liquor mechanically, heat up to a temperature range of 30-100°C, Then use sodium hydroxide solution to neutralize to the end of the reaction, the end point of the reaction is in the pH range of 7 to 10; step 2: carry out liquid-liquid sedimentation and stratification in the temperature range of 40 to 100 ° C; obtain the lower layer product and the upper layer product; Step 3: Separate the salt in the lower product from the mother liquor, and filter while it is hot to remove the salt, and the mother liquor will be used in the next batch; Step 4: Move the oil phase in the upper product into a distillation kettle for vacuum distillation and dehydration to obtain a finished product with a qualified moisture content. It is directly used in the synthesis of m-acetamido-N,N-dimethoxycarbonylmethylaniline. This method has simple technological process, simple operation and control, low waste water generation and high total yield, especially the dehydration and drying time of the product is greatly shortened.

Description

technical field

[0001] The invention belongs to the field of preparation of organic chemical dye intermediate products, and in particular relates to a preparation method of m-aminoacetanilide. Background technique

[0002] Aminoacetanilide is a very important coupling component intermediate in disperse dyes. Mainly used in the synthesis of m-acetamido-N,N-dimethoxycarbonylmethylaniline (referred to as A017), m-acetamido-N,N-diethylaniline and m-acetamido-N,N-diacetoxyethyl Aniline, etc. Traditional m-aminoacetanilide production method: use m-aminoacetanilide hydrochloride as raw material, neutralize with sodium hydroxide solution, then cool, crystallize, filter, wash, and dry to obtain the finished product.

[0003] Specific as figure 1 As shown, there are following deficiencies in the existing preparation scheme:

[0004] 1. The mother liquor can only be used for about 2 to 3 times, and must be discarded when the solubility of sodium chloride and sodium acetate is close...

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