Abstract: The invention relates to a process for preparing diaryl carbonates by reacting monophenols with phosgene or aryl chlorocarbonates with elimination of hydrogen chloride in the presence of mixed hydroxides of elements from groups 2-14 of the periodic table (IUPAC, new) as heterogeneous catalysts.

Abstract: The invention provides a process for preparing diaryl carbonates from dialkyl carbonates and aromatic hydroxyl compounds using at least two reaction columns, a process section for recovering the dialkyl carbonate used in the reaction and for removing the alcohol of reaction, one or more process steps for removing the by-products obtained in the process which have a boiling point between that of the dialkyl carbonate and that of the alkyl aryl carbonate formed during the preparation of the diaryl carbonate, and a process step for further purification of the diaryl carbonate obtained from the reaction columns.

Abstract: Production of an aromatic carbonic ester through an ester exchange reaction between a starting material and a reactant while distilling by-product alcohols and/or by-product dialkyl carbonates off the reaction system, wherein use is made of a specified catalyst.

Abstract: A specific industrially useful process for the production of a high-purity diaryl carbonate in which a diaryl carbonate having low contents of intermediate boiling point and high boiling point impurities is produced is disclosed. As a starting material, a reaction mixture containing an alkyl aryl carbonate obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound is used. The process in which separation by distillation is carried out uses three distillation columns in a specified order. Moreover, it is particularly preferable if a reactive distillation column and the three distillation columns, each of which has a specified structure, and the three distillation columns are each operated under specified distillation conditions.

Abstract: A high-purity diphenyl carbonate, wherein the diphenyl carbonate is unsubstituted or substituted with a lower hydrocarbon, and has a halogen content of not more than 0.1 ppm, a content of an intermediate boiling point material of not more than 100 ppm, and a content of by-products having a higher boiling point than that of said diphenyl carbonate of not more than 100 ppm. A specific industrially useful process for the production of a high-purity diaryl carbonate in which a diaryl carbonate having low contents of intermediate boiling point and high boiling point impurities is produced is disclosed. As a starting material, a reaction mixture containing an alkyl aryl carbonate obtained through a transesterification reaction between a dialkyl carbonate and an aromatic monohydroxy compound is used. The process in which separation by distillation is carried out uses three distillation columns in a specified order.

Abstract: A process for producing a carbonic ester, characterized in that an aromatic monohydroxy compound or an aliphatic monohydroxy compound is subjected to oxidative carbonylation with carbon monoxide and oxygen in the presence of a palladium catalyst using a compound having a carbonate bond as a reaction solvent. A process for producing a polycarbonate, characterized in that an aromatic dihydroxy compound or an aliphatic dihydroxy compound is subjected to oxidative carbonylation with carbon monoxide and oxygen in the presence of a palladium catalyst using a compound having a carbonate bond as a reaction solvent is also described. The carbonic ester can be produced with a higher yield and at a higher reaction rate and, also, a polycarbonate having a higher molecular weight as compared with the conventional method can be produced with a higher yield and at a higher reaction rate.

Abstract: The invention relates to a process for the partial or complete separation of a mixture comprising hydrogen chloride and phosgene, possibly solvents and possibly low boilers and inerts as are typically obtained in the preparation of isocyanates by reaction of amines with phosgene, which comprises firstly carrying out a partial or complete condensation of phosgene, then a distillation or stripping step in a column to remove the hydrogen chloride from the bottom product phosgene and subsequently a scrub of the top product hydrogen chloride by means of the process solvent to absorb the phosgene in the process solvent. An after-purification by means of adsorption on activated carbon or by another suitable method can subsequently be carried out to remove solvent residues.

Abstract: Processes for the alcoholysis, inclusive of transesterification and/or disproportionation, of reactants are disclosed. The alcoholysis process may include feeding reactants and a trace amount of soluble organometallic compound to a reactor comprising a solid alcoholysis catalyst, wherein the soluble organometallic compound and the solid alcoholysis catalyst each independently comprise a Group II to Group VI element, which may be the same element in various embodiments. As an example, diphenyl carbonate may be continuously produced by performing transesterification over a solid catalyst followed by disproportionation, where a trace amount of soluble organometallic compound is fed to the transesterification reactor.

Abstract: A process for the production of alkyltin alkoxides which comprises subjecting at least one alkyltin compound selected from among organotin compounds having tin-oxygen-tin linkages as the starting compound and a hydroxyl compound as the reactant to dehydration to obtain an alkyltin alkoxide corresponding to the starting compound and the reactant, characterized by continuously feeding the starting compound and the reactant into a reactor, discharging a water-containing low boiling point component from the reactor, and continuously withdrawing a reaction fluid containing an alkyltin alkoxide as the bottom from the reactor.

Abstract: Processes comprising: transesterifying a dialkyl carbonate and an aromatic hydroxyl compound in the presence of a transesterification catalyst to provide a diaryl carbonate product comprising the transesterification catalyst as an impurity; subjecting the diaryl carbonate product to distillation in a first distillation column having an upper part and a lower part, wherein the upper part comprises a rectifying section and the lower part comprises a stripping section; and withdrawing a first sidestream from the first distillation column, wherein the first sidestream comprises a purified diaryl carbonate.

Abstract: The invention relates to a process for the preparation of a diaryl carbonate, which comprises: (i) contacting an aromatic non-hydroxy compound with a carboxylic acid of formula HOC(?O)R1 (I), wherein R1 is a hydrocarbyl group, and with an oxygen containing gas in the presence of a catalyst, resulting in water and an aromatic carboxylic acid ester of formula R2OC(?O)R1 (II), wherein R2 is an aryl group originating from the aromatic non-hydroxy compound; and (ii) contacting the aromatic carboxylic acid ester of formula (II) from step (i) with a dialkyl carbonate of formula R3OC(?O)OR4 (III), wherein R3 and R4 are the same or different and are alkyl groups, in the presence of a catalyst, resulting in a diaryl carbonate of formula R2OC(?O)OR2 (IV) and an alkyl carboxylic acid ester of formula R5OC(?O)R1 (V), wherein R5 is R3 or R4.

Abstract: It is an object of the present invention to provide a specific process that enables aromatic carbonates to be produced with high selectivity and high productivity stably for a prolonged period of time on an industrial scale of not less than 1 ton per hour from a dialkyl carbonate and an aromatic monohydroxy compound using two continuous multi-stage distillation columns. Although there have been various proposals regarding processes for the production of aromatic carbonates by means of a reactive distillation method, these have all been on a small scale and short operating time laboratory level, and there have been no disclosures whatsoever on a specific process or apparatus enabling mass production on an industrial scale.

Abstract: The present invention provides a method of remedying deterioration of an insulating film which, during the remedial treatment of an insulating film deteriorated by plasma treatment, does not leave residual remedial agent on the wiring material such as the copper wiring layer, can be conducted using a dry process, and exhibits excellent applicability to mass production. The insulating film that has been deteriorated by plasma treatment is brought into contact with a remedial agent composed of a compound with a molecular structure having at least one of a nitro group and a carbonyl group, and at least one of a hydrocarbon group and a hydrogen group.

Abstract: 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.

Abstract: Processes comprising: reacting a dialkyl carbonate and an aromatic hydroxy compound in the presence of a transesterification catalyst in a first reaction column, the first reaction column comprising a top section, a bottom section, a rectifying section in an upper portion of the column and a reaction zone below the rectifying section; feeding a bottom product from the first reaction column to a further reaction column; the bottom product comprising a diaryl carbonate, an alkylaryl carbonate, or both, and residual unreacted dialkyl carbonate and aromatic hydroxy compound; the further reaction column comprising a top section, a rectifying section in an upper portion of the column and a reaction zone below the rectifying section; and reacting the residual reacted dialkyl carbonate and aromatic hydroxy compound in the further reaction column; feeding a process stream to a distillation column, the process stream comprising a mixture of unreacted dialkyl carbonate and one or more reaction-product alcohols drawn fro

Abstract: An improved method for the preparation of ester-substituted diaryl carbonates prepared by reacting phosgene with recycle streams of ester-substituted phenols from reaction processes using a tetraalkyl ammonium hydroxide catalyst, a tetraalkyl phosphonium hydroxide catalyst, or both, where at least one alkyl group of the tetraalkyl ammonium hydroxide or the tetraalkyl phosphonium hydroxide is a methyl group. The improvement includes the step of treating the recycle stream to reduce the concentration of a trialkyl amine, trialkyl phosphine, or both, if present, from the recycle stream prior to reacting it with phosgene to form the ester-substituted diaryl carbonate.

Abstract: The invention provides a process for the preparation of diaryl carbonates and/or alkylaryl carbonates from dialkyl carbonates and aromatic hydroxy compounds using one or more intermediate condensers for improving heat integration.

Abstract: Diaryl carbonate is prepared by reaction of an aromatic alcohol with a dialkyl carbonate, which dialkyl carbonate has been prepared by the reaction of an alkanol and an alkylene carbonate.

Abstract: The present invention relates to a continuous method for the preparation of an aromatic carbonate by reacting a dialkyl carbonate and an aromatic hydroxy compound in the presence of a heterogeneous catalyst, and a reaction apparatus for the same. The continuous method comprises the step of reacting dialkyl carbonate and an aromatic hydroxy compound in the presence of the heterogeneous catalyst in a loop-type, catalyst-containing reaction apparatus, wherein a reactor equipped with a filter in which the catalyst is contained is connected with a heat exchanger portion for providing necessary heat during the reaction, reaction solution is circulated between the catalyst-containing portion and heat exchanger via a circulation pump, and by-products can be eliminated via a distillation column connected with the reactor.

Abstract: The invention relates to a process for the preparation of a diaryl carbonate by transesterification of an aromatic alcohol with a dialkyl carbonate in the presence of a transesterification catalyst during a period of time [ta], in which the aryl moiety is selected from unsubstituted phenyl and mono-, di- and trisubstituted phenyl groups, in which the alkyl moiety is selected from C2 to C4 linear and branched alkyl groups, in which the catalyst concentration is designated [ca], expressed as gram catalyst per gram of aromatic alcohol and dialkyl carbonate, in which the period of time [tm] and catalyst concentration [cm] are determined to arrive at a pre-set approach to the equilibrium for the transesterification of the aromatic alcohol with dimethyl carbonate to methyl aryl carbonate and methanol, in which the product [ca]*ta is at least 1.5*[cm]*tm under otherwise the same reaction conditions.

Abstract: Production of an aromatic carbonic ester through an ester exchange reaction between a starting material and a reactant while distilling by-product alcohols and/or by-product dialkyl carbonates off the reaction system, wherein use is made of a specified catalyst.

Abstract: A process for producing various organic carbonates by performing transesterification and disproportionation reactions in dual vapor/liquid phase mode preferably in the presence of solid catalyst composition selected from the group consisting of oxides, hydroxides, oxyhydroxides or alkoxides of two to four elements from Group IV, V and VI of the Periodic Table supported on porous material which has surface hydroxyl groups and the method of reactivating catalyst deactivated by polymer deposition by contacting the deactivated catalyst with a solution of hydroxy containing compound in a solvent such as benzene or THF.

Abstract: A method for recovering a product mixture from a waste stream in a diaryl carbonate manufacturing process comprising reacting the waste stream with an alkyl alcohol to form a reaction mixture, and separating the product mixture from the reaction mixture.

Abstract: 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.

Abstract: A method for preparing an aromatic chloroformate comprising, introducing a mixture of at least one aromatic hydroxyl compound, phosgene, at least one solvent, and at least one organic base into a flow reactor to obtain a unidirectionally flowing reaction mixture. The unidirectionally flowing reaction mixture is maintained at a temperature between about 0° C. and about 60° C. to produce a single product stream comprising an aromatic chloroformate.

Abstract: Diphenyl carbonate is produced by reacting phenol with diethyl carbonate in a series of fixed bed reactors each of which is connected at different position on a distillation column via side draw and return streams. The composition of material in a distillation column varies along the length of the column, which is predictable under a given set of conditions of temperature and pressure, thus withdrawing streams at different stages in the column, allows the reactor receiving the feed from a particular stage to be operated under conditions to maximize the desired reaction, while allowing the unreacted or byproduct to go back into the distillation and be sent to a stage (by the equilibrium of the distillation) where they are favorably treated in a reactor.

Abstract: A method for recovering a product mixture from a waste stream in a diaryl carbonate manufacturing process comprising reacting the waste stream with an alkyl alcohol to form a reaction mixture, and separating the product mixture from the reaction mixture.

Abstract: A method and apparatus for continuously producing an alkyl aryl ether and a diaryl carbonate by reacting a dialkyl carbonate and an aromatic alcohol in presence of a transesterification catalyst.

Abstract: Processes for refining dialkyl carbonate-containing compositions are described, wherein a composition comprising a dialkyl carbonate is provided; and the composition is subjected to a rectification wherein low-boiling impurities are removed, and a rectification wherein high-boiling impurities are removed; and subsequently to a deodorization wherein medium-boiling impurities are removed.

Abstract: A method of increasing the amount of diphenylcarbonate produced per amount of catalyst consumed in a phenol carbonylation process is described. Phenolic carbonylation produces water as a reaction product which reduces the turnover number (TON) of the catalyst. A mixture of a phenolic precursor, a base containing catalyst and co-catalyst components and at least one chemical additive comprising a halide or hydroxide of alkali metal or alkaline earth metal when carbonylated together under specific conditions increases the turnover number (TON) and water resistivity of a palladium catalyst. The metal halide likely makes the catalyst less susceptible to degradation by water hence increasing the reaction yield per weight of catalyst consumed.

Abstract: A process for the separation a substantially adduct-free diaryl carbonate from reaction solution is disclosed. The process entails obtaining a solution that contains diaryl carbonate, catalyst system components and an aromatic solvent, lowering the temperature of the solution, optionally in the presence of a nucleating agent, to produce a crystallization product, and washing the crystallization product with an anhydrous wash solution to remove catalyst residues and impurities.

Abstract: High yields of ester-substituted diary carbonates such as bis-methyl salicyl carbonate were obtained by the condensation of ester-substituted phenols with phosgene in the presence of a phase transfer catalyst (PTC) and optionally a tertiary amine catalyst in a solvent free reaction system comprising an aqueous phase held at a pH of 8.3 or higher. The optimized conditions of the present invention use an excess of ester-substituted phenol relative to phosgene and high conversion of phosgene to ester-substituted diaryl carbonate is observed. The product ester-substituted diaryl carbonate may be conveniently isolated as a solid by filtration or as a liquid in which the excess ester-substituted phenols serves as solvent. The method represents an attractive route for the manufacture of bis methyl salicyl carbonate and ester-substituted diaryl carbonates generally. The ester-substituted diaryl carbonates are useful for the preparation and modification of polycarbonates.

Abstract: A thermoplastic polyurethane useful for elastomers, elastic fibers and artificial leathers contains a polyaddition product of a diisocyanate and a chain extender with a liquid polyethercarbonate diol which is a reaction product of a carbonate compound with a polyether diol having structural units (a) (—(CH2)6—O—) and at least one member of structural units (b) (—(CH2)2—O) and (c) (—CH2CH(CH3)—O—), and in which the units (b) are present in an average number (n) of moles of 0 to 5 per mole of the units (a), the units (c) are present in an average number (m) of moles of 0 to 5 per mole of the units (a), and the total average number (n+m) of moles of the units (b) and (c) is more than 1 but not more than 5, per mole of the units (a).

Abstract: A process for producing diaryl carbonate is disclosed. The process entails forming a reaction mixture wherein reacting are an aromatic hydroxy compound corresponding to the formula R—O—H??(II), wherein R denotes a C6-22-aromatic hydrocarbon radical, with CO and O2 in the presence of a catalyst system. The catalyst system contains components a) a Group VIII B metal compound, b) at least one second metal compound, c) a bromide compound, and d) a base. The process entails introduction of one or more of components a) to d) to the reaction mixture in more than one increment in the course of the reaction.

Abstract: The invention relates to a method for the catalytic conversion of organic carbonate to the corresponding alcohol, wherein the organic carbonate is contacted with alcohol and/or water in the presence of a zinc supported catalyst.

Abstract: A method for economically producing aromatic carbonates from aromatic hydroxy compounds is disclosed which in one embodiment comprises the steps of: (i) contacting at a temperature sufficient to keep the mixture molten at least one aromatic hydroxy compound with a catalyst composition comprising the following and any reaction products thereof: (A) at least one Group 8, 9, or 10 metal or a compound thereof; (B) at least one salt; (C) at least one metal co-catalyst; and (D) optionally, at least one activating solvent; (ii) optionally heating the mixture at atmospheric pressure to a temperature above that sufficient to keep the mixture molten; (iii) pressurizing the mixture with carbon monoxide; (iv) optionally heating the mixture under pressure of carbon monoxide to a temperature above that sufficient to keep the mixture molten; (v) optionally maintaining the mixture under pressure of carbon monoxide for a time period; (vi) introducing oxygen to the mixture to a desired concentration of oxygen in carbon monoxid

Abstract: A process for the separation a substantially adduct-free diaryl carbonate from reaction solution is disclosed. The process entails obtaining a solution that contains diaryl carbonate, catalyst system components and an aromatic solvent, lowering the temperature of the solution, optionally in the presence of a nucleating agent, to produce a crystallization product, and washing the crystallization product with an anhydrous wash solution to remove catalyst residues and impurities.

Abstract: A process for the separation a substantially adduct-free diaryl carbonate from reaction solution is disclosed. The process entails obtaining a solution that contains diaryl carbonate, catalyst system components and an aromatic solvent, lowering the temperature of the solution, optionally in the presence of a nucleating agent, to produce a crystallization product, and washing the crystallization product with an anhydrous wash solution to remove catalyst residues and impurities.

Abstract: Aromatic carbonates can be prepared economically and efficiently by reacting an aromatic hydroxy compound with carbon monoxide and oxygen in the presence of a catalyst wherein a palladium compound is supported on a perovskite-type composite oxide represented by the following formula (1) or (1′): M(1−x)M′xM″Oy  (1) (wherein, M is a group IIIB metal; x is a number of 0 to 1; M′ is a metal having an ionic radius of 0.90 Å or more; M″ is Mn, Cr, Co, Fe, Ni or Cu; y is a number of 2.5 to 3.5), or L(1−x)L′xL″Oy  (1′) (wherein, L is a group IIA or IVA metal taking a divalent state in the form of an oxide; x is a number of 0 to 1; L′ is a metal having an ionic radius of 0.90 Å or more; L″ is a group IVA, IVB or IIIB metal taking a tetravalent state in the form of an oxide; y is a number of 2.5 to 3.5), and the palladium accounts for 0.01 to 15% of the catalyst by weight.

Abstract: The present invention provides a method and catalyst composition for carbonylating aromatic hydroxy compounds, comprising the step of contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst composition comprising an effective amount of at least one Group 8, 9, or 10 metal source, an effective amount of a combination of inorganic co-catalysts comprising at least one Group 4 metal source and at least one Group 11 metal source, an effective amount of at least one salt co-catalyst with an anion selected from the group consisting of carboxylate, benzoate, acetate, sulfate, and nitrate, wherein the carbonylation catalyst composition is free of a halide source.

Abstract: An improvement to the melt transesterification reaction of diaryl carbonate with dihydroxy aryl compound is disclosed.

Abstract: A method and catalyst system for economically producing aromatic carbonates from aromatic hydroxy compounds. In one embodiment, the present invention provides a method of carbonylating aromatic hydroxy compounds by contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system that includes an effective amount of a Group VIII B metal source; an effective amount of a bromide composition; an effective amount of an activating organic solvent; an effective amount of a combination of inorganic co-catalysts comprising a lead source and a copper source; and an effective amount of a base.

Abstract: A method and catalyst composition for economically producing aromatic carbonates from aromatic hydroxy compounds is disclosed. The present invention provides a method for carbonylating aromatic hydroxy compounds, comprising the step of contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a halide-free carbonylation catalyst composition comprising an effective amount of at least one Group 8, 9, or 10 metal source, an effective amount of a first inorganic co-catalyst comprising at least one Group 14 metal source, an effective amount of a salt co-catalyst, and optionally an effective amount of a second inorganic co-catalyst selected from the group consisting of a Group 4 metal source, a Group 7 metal source, a Group 11 metal source, and a lanthanide element source, and optionally an effective amount of a base.

Abstract: An improvement to the interfacial boundary process for continuous production of carbonic acid diaryl esters is disclosed. The process that entails a reaction of monophenols in an inert solvent, in the presence of an alkaline solution and a nitrogen base catalyst, is carried out in two stages. In the first stage phosgene, inert solvent and phenol in solution are combined to form a material system and a second stage the reaction to form carbonic acid diaryl ester is completed. The improvement comprising maintaining in the first stage a pH of 11.0 to 12.0 and a temperature below 40° C. and a pH of 7.5-10.5 and a temperature <50° C. in the second stage.

Abstract: A process for the work up of a reaction mixture obtained from the preparation of diaryl carbonate by direct carbonylation of aromatic hydroxy compounds is disclosed. The process entails obtaining a reaction mixture that contains diaryl carbonate, aromatic hydroxy compound, water, base and quaternary salt, separating the mixture in a distillation apparatus having only one theoretical separation stage into a liquid phase and a gas phase and recycling the liquid phase without further work up to the reaction step of the direct carbonylation.

Abstract: The present invention provides a method for making aromatic carbonates. In this method, an aryl alcohol is reacted with a dialkyl carbonate in a reactor (e.g., a distillation column) to produce an arylalkyl carbonate and diaryl carbonate. The total yield of arylalkyl carbonate and diaryl carbonate together is at least 40%. Also, the selectivity of diaryl carbonate versus diaryl carbonate and arylalkyl carbonate together is preferably at least 25%.

Abstract: A process for producing an aromatic carbonate by reacting an aromatic monohydroxy compound with carbon monoxide and molecular oxygen, wherein the reaction is carried out in the presence of: (a) palladium or a palladium compound (component (a)); (b) a redox catalyst (component (b)); (c) a heteropoly-acid or salt thereof (component (c)); and (d) a quaternary ammonium salt or quaternary phosphonium salt (component (d)), and under dehydration conditions. According to the present invention, an aromatic carbonate can be produced from an aromatic monohydroxy compound by a simple process economically and efficiently.

Abstract: The present invention provides a method for making polycarbonates. One embodiment of the method comprises reacting diphenylcarbonate with a dihydric phenol. The diphenylcarbonate is made by reacting a reaction mixture comprising aryl alcohol together with a dialkyl carbonate in a reactor to produce aryl alkylcarbonate and diaryl carbonate.

Abstract: A process for the separation a substantially adduct-free diaryl carbonate from reaction solution is disclosed. The process entails obtaining a solution that contains diaryl carbonate, catalyst system components and an aromatic solvent, lowering the temperature of the solution, optionally in the presence of a nucleating agent, to produce a crystallization product, and washing the crystallization product with an anhydrous wash solution to remove catalyst residues and impurities.

Abstract: High yields of ester-substituted diary carbonates such as bis-methyl salicyl carbonate were obtained by the condensation of methyl salicylate with phosgene in the presence of a phase transfer catalyst (PTC) in an interfacial reaction system in which the pH of the aqueous phase was greater than 9.3. Using the method of the present invention conversions of greater than 99% were obtained whereas under standard conditions using triethylamine as the catalyst conversions were limited to 70-75% of the methyl salicylate starting material even with a 20 mole % excess of added phosgene. The optimized conditions of the of the present invention use only a slight excess of phosgene and represent an attractive route for the manufacture of bis methyl salicyl carbonate and ester-substituted diaryl carbonates generally.