168results about How to "High reaction yield" patented technology

Clean production process of dicamba synthesis midbody

ActiveCN102964221AHigh reaction yieldOrganic chemistryOrganic compound preparationNitrosylsulfuric acidNitroso
The invention relates to a clean production process of a dicamba synthesis midbody, and provides a clean production method of 2,5-dichlorophenol. The clean production process comprises the following steps: stirring 30-70% of dilute sulfuric acid and 2,5-dichloroaniline in a backflow state for 1-2hours, wherein the weight ratio of the dilute sulfuric acid to the 2,5-dichloroaniline is (6:1)-(9:1); after the reaction, cooling the reaction liquid to 0-5 DEG C, and dropping 10-60% nitroso-sulfuric acid and stirring for 2 hours to obtain diazonium liquid, wherein the molar ratio of the 2,5-dichloroaniline to the nitroso-sulfuric acid is 1:(1.0-1.5); carrying out pyrohydrolysis on the synthesized diazonium liquid at 140-170 DEG C to obtain 2,5-dichlorophenol; and carrying out diazotization synthesis on part of the hydrolyzed dilute sulfuric acid subjected to recovery processing as batch charging of dilute sulfuric acid, and synthesizing the other part of the dilute sulfuric with SO2 to be 10-60% nitroso-sulfuric acid, and then applying to diazotization synthesis. According to the synthesis process, no waste salt or phenolic wastewater are generated during diazotization reaction, the reaction yield is as high as 95%, and diazonium liquid is subjected to pyrohydrolysis and the dilute sulfuric acid can be recycled, so that the cycle use of the two can be achieved. The clean production process belongs to a clean and environment-friendly production process.

Preparation method of temperature and pH sensitive shell cross-linked polymeric micelle

InactiveCN102746474AHigh reaction yieldPolymer polydispersity coefficient is smallSolution deliveryPharmaceutical non-active ingredientsChemistryPrecondition
The invention relates to a preparation method of a temperature and pH sensitive shell cross-linked polymeric micelle, characterized by synthesizing a temperature and pH sensitive diblock copolymer by reversible addition-fragmentation chain transfer (RAFT) polymerization, and then using small-molecule dialdehyde or diacid to carry out part crosslinking on the shell structure of a self-assembled polymeric micelle. The method has the characteristics of simpleness, convenience, high preparation yield, no environmental pollution, and the like. The prepared diblock copolymer has the advantages of strong functionality and narrow molecular weight distribution. By using small-molecule cross-linking agent to carry out part crosslinking on the micelle shell structure, under the precondition of guaranteeing the stability of the polymeric micelle, the preparation method has the characteristics of strong feasibility and simple operation, and can reutilize micelles, etc. The obtained temperature and pH sensitive shell cross-linked polymeric micelle has excellent drug loading performance, can rapidly and efficiently adsorb readily degradable or indissoluble drugs under different concentration conditions, is a new generation high performance drug loaded product, and can be applied in the medicine fields of in vivo transfer, gene vectors, and the like.

New technology for producing acrylamide by using ceramic membrane bioreactor

ActiveCN102703535AHigh recovery rateHigh reaction yieldCarboxylic acid amide separation/purificationFermentationUltrafiltrationFermentation broth
The invention relates to a new technology for producing acrylamide by using a ceramic membrane bioreactor. The new technology comprises the following steps of: (1) putting nitrile hydratase thallus fermentation liquor into a ceramic membrane filter for separating and washing thalli; (2) discharging the penetrating liquid of a ceramic microfiltration membrane filter, adding a concentrated and washed nitrile hydratase containing thallus solution serving as a bio-enzyme catalytic agent to an acrylonitrile hydration reaction kettle for catalyzing the hydration reaction of acrylonitrile; and separating and removing an acrylamide product through a ceramic ultrafiltration membrane in the reaction process, and returning the nitrile hydratase containing thallus serving as the bio-enzyme catalytic agent to the reaction kettle for reuse. The new technology has the advantages that the ceramic membranes can remove impurities in the acrylamide product in high precision and timely move away the acrylamide product and can also achieve the purpose of effectively separating thalli and residues of the fermentation liquor, thereby greatly increasing the recovery rate of fermentation liquor thalli and the selectivity and purity of objective products of the following process.

Novel synthetic method for tofacitinib intermediate (3R,4R)-N,4-dimethyl-1-benzyl-3-piperidinamine and oxalate hydrates of (3R,4R)-N,4-dimethyl-1-benzyl-3-piperidinamine

The invention relates to a novel synthetic method for tofacitinib intermediate (3R,4R)-N,4-dimethyl-1-benzyl-3-piperidinamine and oxalate hydrates of (3R,4R)-N,4-dimethyl-1-benzyl-3-piperidinamine. The method comprises the following steps: 3-amino-4-methylpyridine is taken as a starting material, amino of 3-amino-4-methylpyridine is subjected to a reaction with ortho-formate, imino formate is generated, and after simple concentration, an N-methyl derivative is obtained by reduction with metal borohydride; after Boc protection, quaternary ammonium salt is generated from a product and benzyl halide and reduced by metal borohydride, a product is subjected to selective hydrogenation with an Rh catalyst, a compound with rich (3R,4R-rel-) configuration is formed, deprotection, salifying and resolution are performed by a hydrochloric acid/alcohol system for removing a (3R,4S-rel-) isomer pair, an obtained (3R,4R-rel-) configuration product is subjected to free treatment and resolved by L-DTTA, and a 3R,4R- configuration product is obtained; after free treatment of salt obtained after resolution, oxalate is formed and purified, a small quantity of remaining 3S,4S-isomers are further removed, and corresponding (3R,4R)-N,4-dimethyl-1-benzyl-3-piperidinamine with high purity and high optical purity is obtained. Through the adoption of the method, safe, simple and industrial large-scale preparation of the tofacitinib intermediate (3R,4R)-N,4-dimethyl-1-benzyl-3-piperidinamine oxalate hydrates is better facilitated.
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