40results about How to "The synthesis process is reasonable" patented technology

The invention discloses an aromatic diamine type cyano group-containing benzoxazine resin and its preparation method. The benzoxazine resin belongs to the aromatic diamine type, its monomer main chain contains benzene rings and ether bonds, and the ends of the main chain contain cyano groups. A cured monomer has high heat resistance, high rate of combustion carbon residue, and certain toughness, thus being suitable for manufacturing high temperature resistant and flame retarding materials. The preparation method of the aromatic diamine type cyano group-containing benzoxazine resin takes an aromatic diamino compound, cyano group-containing monohydric phenol and formaldehyde as reaction raw materials to synthesize a benzoxazine monomer, which is then subjected to curing and crosslinking so as to obtain the benzoxazine resin. The monomer of the resin has reasonable synthesis process, high purity, high yield and low cost. And the monomer for synthesizing the aromatic diamine type cyano group-containing benzoxazine resin has a structural formula as the following.

The present invention relates to a kind of synthesis method of 2-amino-6-chloropurine (1), comprising the following steps in turn: first drop phosphorus oxychloride into N,N-dimethylformamide at low temperature to form a mixed solution, Then drop into the 1,2-dichloroethane of guanine (2) and react to obtain 2-dimethylaminomethenimino-6-chloropurine (3); the reaction product (3) is dropped into water, and The organic phase is recovered and used mechanically, the pH of the aqueous phase is adjusted to 3 to 5 with an alkali metal hydroxide solution, and the reaction is heated to obtain a wet product of 2-formylamino-6-chloropurine (4); the wet product of the above reaction product (4) is then The hydrolysis reaction is carried out in an alkali metal hydroxide solution, and then the pH value is adjusted with hydrochloric acid to obtain the crude product of 2-amino-6-chloropurine (1), and finally purified to obtain the fine product of the target product (1).

In the present invention, TIME group is formed by residue of the following molecular structures, compound II is used to act with developer oxide to release TIME-PUG group when compound is used in developing process, TIME-PUG grou is cracked on TIME-PUG group under certain condition to realease PUG group for improving photographic performance of the film.

The invention provides a benzylthio acetamido acetylpyrazine triazole derivative. A target compound (I) is obtained by condensing a sulfydryl acetamido acetic acid derivative and a benzyl chloride derivative, condensing the condensed derivatives and 2-piperazinone, reacting the obtained condensed product and trimethyloxonium tetrafluoroborate so as to obtain a methoxy imide compound, and carryingout cyclization on the methoxy imide compound and hydrazine, trifluoroaceticanhydride, acetic anhydride, propionic anhydride, trifluoroacetyl chloride, acetyl chloride or acrylyl chloride. The preparation method provided by the invention has the advantages of reasonable design, stable process, easily obtained raw materials for production, no use of high pressure hydrogenation and good production feasibility. By using the benzylthio acetamido acetylpyrazine triazole derivative provided by the invention, dipeptidyl peptidase-IV (DPP-4) can be selectively inhibited; an effect of reducing blood sugar is obtained; and the derivative can be applied to the preparation of drugs for reducing the blood sugar and has the following structural formula (I).

The invention discloses a method for preparing 2,5-dichlorophenol. The method is formed by using o-chlorophenol as a raw material, adopting a composite catalyst, protecting a hydroxyl group with an acidic substance, and then chlorinating and hydrolyzing it. The new method of the present invention for preparing 2,5-dichlorophenol has lower cost of raw materials than the existing production methods in the market, safe and convenient operation, and is more friendly to the environment; less waste, high yield, suitable for industrial production, Product quality meets international standards.

The invention discloses a preparation method of diphenyl sulfide. The method is as below: adding a certain amount of sodium sulfide in a reaction container; keeping the negative pressure at less than or equal to -0.098 MPa, and slowly heating to 190-220 DEG C; dropwise adding a solvent with insulation, stirring, transferring the sodium sulfide solution while hot to an autoclave, then dropwise adding chlorobenzene while stirring in 1.5-2.5 h, covering the lid, and displacing the air with nitrogen two times; slowly heating to 190 to 240 DEG C while stirring, preserving the temperature and stirring for reaction; slowly cooling, filtering solid, recovering the solvent, purifying and distilling to obtain diphenyl sulfide. The novel method of the invention uses chlorobenzene and sodium sulfide as raw materials to prepare diphenyl sulfide by using. Compared with the prior art in the market, the method has the advantages of low raw material cost, safe and convenient operation, environment-friendliness, less three wastes and high yield, and is suitable for industrial production; and the product quality is in line with international standards.