Process for production of diaryl oxalate

A technology of diaryl oxalate and dialkyl oxalate, which is applied in the direction of carbonate/haloformate preparation, organic chemical methods, chemical instruments and methods, etc., can solve the problems of increased impurities, reduced selectivity, and material Thinning and other issues, to achieve the effect of increased selectivity, improved reaction efficiency, and simplified manufacturing equipment

Active Publication Date: 2012-10-03
UBE IND LTD
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  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

[0010] In addition, in the above-mentioned production method, by using a multi-stage distillation column, the reaction, purification and separation operations were carried out. The present inventors studied the production method and found that although the reaction liquid does not contain a compound containing a halogen atom, the Corrosion and thinning of the material are also found in the reaction liquid contact parts such as distillation towers, storage tanks, piping, etc. made of austenitic stainless steel such as SUS304 specified in JIS G 4304, which is generally used as the material of distillation towers. manufacturing difficulties
[0011] In addition, the alkyl alcohol distilled off in the above production method is mixed with low-boiling impurities generated during the transesterification reaction. If they are recycled to the dialkyl oxalate production process, the yield and selectivity of the production reaction will be affected. Undesirable state such as reduction of performance, increase of generated impurities, etc.

Method used

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  • Process for production of diaryl oxalate
  • Process for production of diaryl oxalate
  • Process for production of diaryl oxalate

Examples

Experimental program
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Effect test

Embodiment

[0190] The present invention is illustrated in detail by way of examples below. However, the present invention is not limited to the following examples at all.

Synthetic example 1

[0192] Synthesis of tetraphenoxytitanium

[0193] 300 ml of phenol was charged at the bottom of a flat-bottomed flask with an inner diameter of 32 mm and an Oldershaw type reactive distillation column (hereinafter referred to as "reactive distillation column for catalyst synthesis") having a volume of 1 L, and heated with an oil bath to raise the temperature. After the temperature distribution in the reactive distillation tower for catalyst synthesis was stabilized while maintaining the total reflux state, phenol was fed at a flow rate of 342.4g / h, and titanium tetraisopropoxide (TIPT) was fed at a flow rate of 21.6g / h . The ratio of the number of moles of phenol fed to the number of moles of Ti atoms in the TIPT (phenol / Ti) was 48. Keeping the reflux ratio at 5 the distillate from the top was withdrawn. In addition, it was continuously withdrawn from the bottom of the reaction distillation column for catalyst synthesis so that the liquid level at the bottom was maintained a...

Synthetic example 2～4

[0198] Synthesis of tetraphenoxytitanium

[0199] The same experiment as in Synthesis Example 1 was performed by changing some of the conditions shown in Table 1, and the results are shown in Table 1.

[0200] In addition, in the reaction solution of Synthesis Example 4, TPT was partially separated.

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Abstract

Disclosed is a process for producing a diaryl oxalate, which involves a step of carrying out the transesterification reaction of a dialkyl oxalate or/and an alkylaryl oxalate with an aryl alcohol in the presence of a tetra(aryloxy)titanium that serves as a catalyst. The process is characterized in that the tetra(aryloxy)titanium is supplied to a reaction system to be used for the transesterification reaction in the form of a solution of the tetra(aryloxy)titanium in an aryl alcohol, wherein the solution is produced by reacting an tetraalkoxytitanium with an excess amount of the aryl alcohol and removing an alkyl alcohol that is produced as a byproduct.

Description

technical field [0001] The present invention relates to a method for producing a diaryl oxalate by transesterifying a dialkyl oxalate or / and an alkylaryl oxalate with an aryl alcohol, and the like. Background technique [0002] Diaryl oxalate can be used as a raw material of diaryl carbonate which has been widely used as a monomer in the production of polycarbonate by the melt method by decarbonylation, and is a compound attracting attention in recent years. Diaryl oxalate can be produced by transesterifying dialkyl oxalate and aryl alcohol, and dialkyl oxalate used at this time can be produced from carbon monoxide and alkyl nitrite. [0003] A series of methods for producing diaryl carbonate from carbon monoxide and alkyl nitrite via dialkyl oxalate and diaryl oxalate have been proposed (see Patent Document 1). [0004] In addition, a method for producing diaryl oxalate has been proposed, which is characterized in that dialkyl oxalate and aryl alcohol are subjected to a tr...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C67/03C07C68/00C07C69/36C07C69/96C08G64/30C07B61/00
CPCC07C67/03C08G64/307C07C68/00C07C69/36C07C69/96
Inventor 田中秀二井伊宏文
Owner UBE IND LTD
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