203results about "Preparation from phosgene or haloformates" patented technology

An environmentally beneficial method of producing methanol from varied sources of carbon dioxide including flue gases of fossil fuel burning powerplants, industrial exhaust gases or the atmosphere itself. Converting carbon dioxide by electrochemical reduction produces formic acid acid and some formaldehyde and methanol mixtures. The formic acid can be used as source of carbon as well as hydrogen to produce methanol, dimethyl ether and other products.

The invention provides a process for the preparation of a compound of Formula 1,

comprising coupling a carboxylic acid of Formula 2

with an aniline of Formula 3

in the presence of a coupling agent.

The present invention provides a salicylic acid ester derivative having an impurity content lower than a specific level and expressed by the following formula (1)(in the formula, R1 is methyl group or ethyl group, R2, which may be substituted optionally, is an alkyl group having a carbon number of from 1 to 30, alkoxy group having a carbon number of from 1 to 30, aryl group having a carbon number of from 6 to 30, aryloxy group having a carbon number of from 6 to 30, aralkyl group having a carbon number of from 6 to 30 or aralkyloxy group having a carbon number of from 6 to 30). The salicylic acid ester derivative is effective as a terminal blocking agent or a polymerization. promoting agent for a polycarbonate, and gives a polycarbonate having good color tone and suitable for optical material use.

Processes comprising: (a) reacting phosgene and a monohydroxyl aryl compound in the presence of a suitable catalyst to form a diaryl carbonate and a solution comprising an alkali chloride; (b) separating the diaryl carbonate from the solution; (c) adjusting the pH of the solution to a value of less than or equal to 8 to form a pH-adjusted solution; (d) treating the pH-adjusted solution with an adsorbent to form a treated solution; (e) subjecting at least a portion of the treated solution to electrochemical oxidation to form chlorine and an alkali hydroxide solution; and (f) recycling at least a portion of one or both of the chlorine and the alkali hydroxide solution.

In the presence of an imide compound (e.g., N-hydroxyphthalimide) shown by the formula (2):wherein R1 and R2 independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cycloalkyl group; or R1 and R2 may bond together to form a double bond or an aromatic or non-aromatic ring; Y is O or OH and n=1 to 3;or the imide compound and a co-catalyst (e.g., a transition metal compound), an adamantane derivative having a functional group such as a nitro group, an amino group, a hydroxyl group, a carboxyl group, a hydroxymethyl group and an isocyanato group is oxidized with oxygen. According to the above method, an adamantane derivative having a hydroxyl group together with a functional group such as a nitro group, an amino group, a hydroxyl group, a carboxyl group, a hydroxymethyl group and an isocyanato group is efficiently obtained.

The invention relates to a process for production of diaryl carbonate combined with the electrolysis of the resultant alkali metal chloride-containing process wastewater. The process according to the invention makes possible, inter alia, improved utilization in electrolysis of the alkali metal chloride-containing solution obtained in the production of diaryl carbonate.

The present invention relates to nitric oxide releasing prodrugs of known drugs or therapeutic agents which are represented herein as compounds of formula (I) wherein the drugs or therapeutic agents contain one or more functional groups independently selected from a carboxylic acid, an amino, a hydroxyl and a sulfhydryl group. The invention also relates to processes for the preparation of the nitric oxide releasing prodrugs (the compounds of formula (I)), to pharmaceutical compositions containing them and to methods of using the prodrugs.

The present invention relates to an interfacial method of preparing ester-substituted diaryl carbonates. The method includes the steps of: forming a reaction mixture comprising phosgene, an ester-substituted phenol, an organic solvent, and a catalyst selected from the group consisting of a tertiary amine catalyst and a phase transfer catalyst, said reaction mixture having an organic phase and an aqueous phase, wherein said aqueous phase has a brine strength; allowing the reaction mixture to react wherein during the reaction, (i) the aqueous phase has a pH, and the pH is adjusted, if necessary, by the addition of an alkali metal hydroxide solution in amounts such that the pH is greater than or equal to 9.0 during at least some portion of the reaction, and (ii) the brine strength of the aqueous phase is adjusted, if necessary, by varying the concentration of the alkali metal hydroxide solution being added to maintain the pH such that the brine strength is between 15% and a saturated brine solution during at least some portion of the reaction: thereby forming an ester-substituted diaryl carbonate, wherein the reaction mixture is formed with less than 15% water of formulation, and wherein the brine strength is maintained at or above 15% and the pH is maintained at or above 9 for a sufficient portion of the process that the ester-substituted diaryl carbonate is formed with a conversion of at least 90% and a selectivity of at least 98%.

This invention discloses a method for preparing di-tert-butyl dicarbonate. The method comprises: (1) stirring sodium tert-butoxide and hexane for cooling; (2) introducing CO2, and keeping the temperature at 5-15 deg.C; (3) adding bis(trichloromethyl) carbonate or trichloro methyl chloroformate; (4) keeping the temperature, and adjusting the pH to 5-6; (5) adding water, keeping the temperature at 0-5 deg.C, stirring and wshing with water to neutrality; (6) removing the solvent under normal pressure to 80-90 deg.C, and cooling to room temperature; (7) freezing and crystallizing; (8) separating and drying by centrifuging; (9) placing the dried material in a kettle, keeping the temperature at 25-30 deg.C, stirring, evacuating to -0.095 MPa, discharging and storing at -5-10 deg.C. The method uses chloroformate as a substitute for sulfuryl chloride, thus has such advantages as easy operation, little waste, high yield and high product purity, and is suitable for mass production.

The invention relates to a tobacco humectant, discloses a monosaccharide geraniol carbonate diester compound, and further discloses a preparation method for the monosaccharide geraniol carbonate diester compound. According to the present invention, the effects of humidity preserving, damp proofing, slow perfume releasing and sensory evaluation of the monosaccharide geraniol carbonate diester compound adopted as the tobacco humectant are tested. The test results show that: the monosaccharide geraniol carbonate diester compound provides the humidity preserving property for the tobacco, and has effects of aroma increasing, uniform aroma releasing and improvement of organoleptic quality of the tobacco. In the formula provided by the present invention, O-R-O represents a residue of five-carbon or six-carbon monosaccharide, the two geraniol carbonate structure units are positioned on any two possible locations of the five-carbon or six-carbon monosaccharide.

The invention provides methods of synthesizing a viral protease inhibitor in high yield, without using expensive catalysts or challenging reaction conditions.

The invention provides a method for synthesizing chlorinated formic acid 9-fluoren methyl, which comprises the following steps: (1) 9-fluoren methyl and triphosgene are reacted for 0.5 to 3 hours in ice bath, under the existence of catalyst and in organic solvent; the catalyst is chosen from N with nucleophilicity, N-dimethylformamide, acetone, diisopropyl ethyl amine, diethylamine, triethylamine, ethyleendiamine, putrescine, imidazole, and the solvent is chosen from benzene, toluene, cyclohexane, hexane, heptane, cyclopentane, dichloromethane, chloroform and the compound thereof; (2) the temperature raises to 20 to 50 DEG C, and the mixture reacts for 1 to 5 hours. The method for synthesizing chlorinated formic acid 9-fluoren methyl adopts safe solid phosgene as reactant, and is simple in technique, convenient in safety, mild in condition, high in yield and easy in realization of industrialization production; the solvent can be used repeatedly after being processed simply, and the products do not need to be refined, and purity is up to more than 98 percent.

In an embodiment, a method of producing a carbonate comprises reacting carbon monoxide and chlorine in a phosgene reactor in the presence of a catalyst to produce a first product comprising phosgene; wherein carbon tetrachloride is present in the first product in an amount of 0 to 10 ppm by volume based on the total volume of phosgene; and reacting a monohydroxy compound with the phosgene to produce the carbonate; wherein the phosgene reactor comprises a tube, a shell, and a space located between the tube and the shell; wherein the tube comprises one or more of a mini-tube section and a second tube section; a first concentric tube concentrically located in the shell; a twisted tube; an internal scaffold; and an external scaffold.

The present invention relates to a process for the continuous preparation of diaryl carbonates from phosgene and at least one monohydroxy compound (monophenol) in the presence of catalysts, and also the use thereof for preparing polycarbonates. The hydrogen chloride formed in the reaction is converted by thermal oxidation into chlorine, with the chlorine being recirculated to the preparation of phosgene. In particular, the process comprises utilization of the hydrogen chloride formed for the process for preparing diphenyl carbonate (DPC process).

The present invention discloses an improved method for the preparation of alky/aryl chloroformates directly from alcohols and triphosgene. This method is simple, mild and efficient avoids use of hazardous phosgene. It can be used for the preparation of various aryl as well as alkyl chloroformates in excellent yields.

Carbonates of anti-aging ingredients, in particular anti-oxidants and skin illuminating phenol ingredients, have been prepared as derivatives of these ingredients with enhanced physical properties. It has been demonstrated that these carbonates will hydrolyze under enzymatic catalysis to release the parent ingredient. In contrast, esters of the phenolic groups in many cases do not hydrolyze under the same conditions.