摘要:
A process for catalytic production of diaryl carbonates by oxidative carbonylation of aromatic hydroxy compounds with carbon monoxide and oxygen achieves water removal during reaction by a process comprising the steps of: removing a liquid stream from an oxidative carbonylation reaction mixture in a reaction vessel, subjecting the liquid stream to reduced pressure, and returning at least a portion of dried liquid stream to the reaction vessel. Typical catalyst systems for oxidative carbonylation contain (A) at least one Group 8, 9, or 10 metal having an atomic number of at least 44 or a compound thereof; (B) at least one alkali metal salt; (C) at least one metal co-catalyst; (D) at least one activating organic solvent; and (E) optionally, at least one base.
摘要:
A process for catalytic production of diaryl carbonates by oxidative carbonylation of aromatic hydroxy compounds with carbon monoxide and oxygen achieves water removal during reaction by a process comprising the steps of: removing a liquid stream from an oxidative carbonylation reaction mixture in a reaction vessel and transferring the stream to a disengagement vessel, transferring a stream from the disengagement vessel to a flash vessel and subjecting the liquid stream to reduced pressure, and returning at least a portion of dried liquid stream to the reaction vessel. Typical catalyst systems for oxidative carbonylation contain (A) at least one Group 8, 9, or 10 metal having an atomic number of at least 44 or a compound thereof; (B) at least one guanidinium salt or onium salt; (C) at least one metal co-catalyst; and (D) at least one base.
摘要:
A process for catalytic production of diaryl carbonates by oxidative carbonylation of aromatic hydroxy compounds with carbon monoxide and oxygen achieves water removal during reaction by a process comprising the steps of: removing a liquid stream from an oxidative carbonylation reaction mixture in a reaction vessel, subjecting the liquid stream to reduced pressure, and returning at least a portion of dried liquid stream to the reaction vessel. Typical catalyst systems for oxidative carbonylation contain (A) at least one Group 8, 9, or 10 metal having an atomic number of at least 44 or a compound thereof; (B) at least one guanidinium salt or onium salt; and (C) at least one metal co-catalyst.
摘要:
A process for catalytic production of diaryl carbonates by oxidative carbonylation of aromatic hydroxy compounds with carbon monoxide and oxygen achieves water removal during reaction by a process comprising the steps of: removing a liquid stream from an oxidative carbonylation reaction mixture in a reaction vessel, subjecting the liquid stream to reduced pressure, and returning at least a portion of dried liquid stream to the reaction vessel. Typical catalyst systems for oxidative carbonylation contain (A) at least one Group 8, 9, or 10 metal having an atomic number of at least 44 or a compound thereof; (B) at least one alkali metal salt; (C) at least one metal co-catalyst; (D) at least one activating organic solvent; and (E) optionally, at least one base.
摘要:
The present invention is directed to a method for reducing the percent decomposition of an aromatic carbonate in a first reaction mixture comprising the aromatic carbonate, the method comprising the step of adding at least one decomposition-reducing additive to the first reaction mixture, so as to produce a second reaction mixture in which the percent of the aromatic carbonate present in the second reaction mixture after a predetermined amount of time is greater than the percent of the aromatic carbonate that would be present in the first reaction mixture in the absence of adding the decomposition-reducing additive, after the same predetermined amount of time.
摘要:
Bromide source such as alkali metal bromide, alkaline earth metal bromide, or onium bromide, present as part of a catalyst mixture in an organic oxidative carbonylation mixture further comprising diaryl carbonate and a hydroxyaromatic compound, is often at least partially converted to organic bromide such as bromophenols. The bromide source can be recycled after reaction through treatment with an aqueous acidic bromide solution such as hydrogen bromide, preferably after removal of a major proportion of hydroxyaromatic compound such as phenol.
摘要:
Hydroxyaromatic compounds such as phenol are carbonylated with oxygen and carbon monoxide in the presence of a catalyst system comprising a Group VIII metal, preferably palladium; at least one bromide or chloride salt, preferably sodium bromide or a tetraalkylammonium bromide; at least one organic bisphosphine such as 1,3-bis(diphenylphosphino)propane or 1,4-bis(diphenylphosphino)butane; and a compound of a metal other than a Group VIII metal having an atomic number of at least 44, preferably a lead bromophenoxide. There may also be present a polar organic liquid as a cosolvent.
摘要:
Hydroxyaromatic compounds such as phenol are carbonylated with oxygen and carbon monoxide in the presence of a catalyst system comprising a Group VIIIB metal, preferably palladium; at least one bromide or chloride salt, preferably sodium bromide or a tetraalkylammonium bromide; at least one organic bisphosphine such as 1,3-bis(diphenylphosphino)propane or 1,4-bis(diphenylphosphino)butane; and a compound of a metal other than a Group VIII metal having an atomic number of at least 44, preferably a lead bromophenoxide. There may also be present a polar organic liquid as a cosolvent.
摘要:
A method for preparing hydroxyaromatic compounds brominated in the para-position, such as p-bromophenol, is disclosed. The method yields overall high process selectivity through isomeric equilibration and separation of the brominated products, thereby eliminating the need for high para selectivity in the products of catalytic oxybromination reactions of hydroxyaromatic compounds using oxygen, a bromine source, and an acidic medium in the presence of a metal catalyst. Furthermore, the invention provides an efficient method for recycling the metal catalyst, as well as reagents used in the bromination, to further reactions.
摘要:
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 monoxide; (vii) starting gas flow to the mixture at a desired concentration of oxygen and carbon monoxide; (viii) optionally maintaining gas flow for a time period at less than a desired ultimate temperature for the mixture; and (ix) optionally heating the mixture to a desired ultimate temperature under flow of gases.