8 results about "Propyl bromide" patented technology

The invention belongs to the field of high polymer materials, and relates to a clean construction method of a halogen-free phosphorus-free flame-retardant epoxy polymerization system. The preparation method comprises the following steps: preparing an intermediate I from 2, 2 '-diallyl bisphenol and allyl bromide under the action of potassium carbonate; carrying out rearrangement reaction on the intermediate I to prepare an intermediate II; and carrying out etherification and ring-closure reaction on the intermediate II and epoxy chloropropane under the action of a catalyst and sodium hydroxide to obtain the epoxy resin monomer III. The halogen-free phosphorus-free flame-retardant epoxy resin polymer is obtained by mixing an epoxy resin monomer with a curing agent, melting, performing injection molding and curing. The halogen-free and phosphorus-free flame retardant polymer obtained by the invention can reach the flame retardant grade of UL94-V0 grade.

This invention provides a ( E This invention relates to the field of pharmaceutical synthesis technology and provides a method for synthesizing 3,5-dihydroxy-4-isopropylstilbene. The method comprises three steps: starting with 3,5-dimethoxy-bromobenzene as a starting material, isopropylation is carried out under acidic conditions to obtain 3,5-dimethoxy-4-isopropylstilbene; further, a Heck reaction is performed with styrene under palladium catalysis to obtain (…). E )-3,5-dimethoxy-4-isopropylstilbene; demethylation reaction yields the ( E 3,5-Dihydroxy-4-isopropylstilbene. Compared to existing synthetic routes, the synthetic method of this invention significantly shortens the synthetic path, has higher atom utilization, higher product yield, and is environmentally friendly.

The invention provides a preparation method of octabromoS ether, and belongs to the technical field of flame-retardant materials. According to the preparation method, bisphenol S and allyl bromide are subjected to a carbon-oxygen coupling reaction under catalysis of a transition metal compound catalyst, bisphenol S diallyl ether and hydrogen bromide are obtained, hydrogen bromide can be recycled in a subsequent addition reaction, and the cost is saved; then hydrobromic acid and bisphenol S diallyl ether are subjected to an addition-electrophilic substitution reaction under catalytic oxidation of hydrogen peroxide to obtain octabromo-S ether, and high-toxicity bromine is not adopted; hydrogen peroxide is reduced into water in the reaction, so that the method is green and environment-friendly.

This invention provides a ZSM-48 and ZSM-5 composite molecular sieve, its preparation method, and its application. The method includes: mixing a template agent, a silicon source, an aluminum source, water, and an alkali source in a molar ratio of (0.01-0.5):1:(0.005-0.05):(10-100):(0.03-0.2) to obtain an initial gel; the template agent is tetrapropylammonium bromide and / or hexamethyldiammonium bromide; adding seed crystals to the initial gel and crystallizing to obtain a crystallized product; the seed crystals are ZSM-5 molecular sieve and / or ZSM-48 molecular sieve, with a mass ratio of seed crystal to silicon source of (0.01-0.2):1; calcining and ammonium exchange of the crystallized product to obtain the ZSM-48 and ZSM-5 composite molecular sieve. This invention significantly improves product purity and inhibits the formation of impurity crystals while ensuring the relative crystallinity of the composite molecular sieve by introducing heterogeneous seed crystals and a two-step crystallization process.

The invention provides a preparation method of spirolactone, and relates to the technical field of organic synthesis. The preparation method of spirolactone provided by the invention comprises the following steps: taking 4-androstene-3, 17-diketone as a raw material, carrying out nucleophilic addition reaction on the 4-androstene-3, 17-diketone and an organic zinc reagent 3-tert-butoxy-3-oxypropyl zinc bromide, then carrying out elimination-lactonization under the catalysis of trifluoroacetic acid, and completing lactonization while removing tert-butyl; then sequentially carrying out etherification reaction and oxidative dehydrogenation reaction to obtain canrenone, and finally carrying out addition reaction on canrenone and thioacetic acid to obtain spirolactone. The preparation method provided by the invention provides a novel construction method of 21-carboxylic acid-gamma-lactone, the method is good in specificity, the total mass yield of spirolactone is greater than 92%, and the total mass yield is high; moreover, the HPLC purity of the spirolactone prepared by the preparation method provided by the invention is greater than 99.7%, which is far higher than the purity of the spirolactone prepared by the existing process.

The invention belongs to the technical field of chemical synthesis, and particularly relates to a preparation method of 2-(4-(cyclopropyl formyl) phenyl)-2-methyl tert-butyl propionate 13C. Comprising the following steps: introducing carbon dioxide (13C) into tetrahydrofuran and a reagent A at-80 DEG C to synthesize cyclopropanecarboxylic acid (13C), wherein the reagent A is cyclopropyl magnesium bromide and cyclopropyl magnesium iodide: adding the cyclopropanecarboxylic acid (13C), dichloromethane, dimethyl hydroxylamine hydrochloride and 4-dimethylaminopyridine into triethylamine at room temperature, and reacting at the temperature of-80 DEG C to obtain the cyclopropanecarboxylic acid (13C). The preparation method comprises the following steps: synthesizing N-methoxy-N-methyl cyclopropanecarboxamide-13C from 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride; the preparation method comprises the following steps: adding 2-(4-bromophenyl)-2-tert-butyl methyl propionate and tetrahydrofuran into a reaction kettle, dropwise adding an alkali solution at the temperature of-40 DEG C, and dropwise adding N-methoxy-N-methylcyclopropanecarboxamide-13C to synthesize 2-(4-(cyclopropanecarboxyl) phenyl)-2-tert-butyl methyl propionate-13C, thereby obtaining the 2-(4-(cyclopropanecarboxyl) phenyl)-2-tert-butyl methyl propionate-13C. The method is reasonable in route, low in cost, high in yield and easy to industrialize.

The application discloses a method for hydrogen sulfide resource utilization by using surfactant-induced modified zeolite to catalyze butene and hydrogen sulfide to synthesize butyl mercaptan. The surfactant-induced modified zeolite is prepared by the following steps: dissolving 0.3-0.4g of cetyl tripropyl ammonium bromide in 0.06-0.1mol / L of NaOH aqueous solution, then adding 1-1.2g of FAU type zeolite, stirring for 1-2h at room temperature, transferring the mixture into a high-pressure reaction kettle, heating for 30-90h at 150-170 DEG C, performing solid-liquid separation, calcining the solid at 500-700 DEG C for 3-5h, and then using an equal-volume impregnation method to place the calcined solid in a molybdate solution, standing, and drying to obtain the surfactant-induced modified zeolite. The catalyst has the advantages of good stability, good sulfur resistance and high selectivity, and the service life of the catalyst is greatly improved.

The invention relates to the technical field of agricultural disease control, in particular to application of indole compounds and pharmaceutically acceptable salts, solvates, crystal forms, prodrugs, stereoisomers and tautomers thereof in preparation of drugs for inhibiting pathogenic fungi pathogenic key protein kinase CgSlt2. The invention provides a novel CgSlt2 targeting inhibitor for the first time, in particular, indole compounds ((S)-N-(1-(1H-indol-3-yl)-4-(methylamino)-4-oxobutyl-2-yl)-8-bromine-1, 6-naphthyridine-2-formamide) and ((S)-N-(2-((1H-indol-3-yl)-1-(methylamino)-1-oxopropyl)-8-bromine-1, 6-naphthyridine-2-formamide) are subjected to a one-pot reaction to prepare the CgSlt2 targeting inhibitor. The CgSlt2 inhibitor (2, 6-naphthyridine-2-formamide) has the characteristics of strong target property and high activity, and shows excellent pathogenicity for inhibiting colletotrichum gloeosporioides complex strains.