Method of producing terephthalic aldehyde

FIELD: chemistry.

SUBSTANCE: terephthalic aldehyde is obtained from α,α,α',α'-tetrabromo-p-xylene while heating, followed by extraction of the end product. The method includes reacting α,α,α',α'-tetrabromo-p-xylene with O,O-dimethyl methylphosphonate at 180°C, and the end product is extracted from the reaction mass with isooctane.

EFFECT: method enables to obtain an end product with high output using a simple technique.

2 ex

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of producing high-purity, halogen-free o-phthalaldehyde, having gas chromatography (GC) purity >99.5% of area, which can be used as an intermediate compound in production of paint, optical clarifying agent, in biocidal industry or photography. The disclosed method comprises the following steps: a) hydrolysis of tetrahalo-o-xylene at temperature 155-160°C and pressure 2-5 bars to o-phthalaldehyde which is b) converted in an acidic alcohol solution at temperature ranging from 0°C to boiling point with a reflux condenser to the corresponding dialkoxyphthalane and further, c) acetal is decomposed via acid hydrolysis at pH ranging from >1.5 to 7, thereby obtaining highly pure, halogen-free o-phthalaldehyde.

EFFECT: efficient method of producing high-purity, halogen-free o-phthalaldehyde.

5 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a separation method intended for removing acetone from a mixture comprising acetone, methyl acetate and methyl iodide. The method includes the following steps: (a) feeding said stream comprising acetone, methyl acetate and methyl iodide into a first distillation zone; (b) feeding acetic acid into said first distillation zone, either by addition of acetic acid to said stream comprising acetone, methyl acetate and methyl iodide or by feeding acetic acid directly to the first distillation zone at one or more points at or above the point of feeding said stream comprising acetone, methyl acetate and methyl iodide into the first distillation zone at step (a), or a combination of both; (c) removing from the first distillation zone a light fraction stream comprising methyl iodide and a heavy fraction stream comprising acetone, methyl acetate, acetic acid, and a reduced amount of methyl iodide; (d) feeding into a second distillation zone the heavy fraction stream from step (c); (e) removing from the second distillation zone a light fraction stream comprising methyl acetate and methyl iodide and a heavy fraction stream comprising acetone, methyl acetate and acetic acid; (f) feeding the heavy fraction stream from step (e) into a third distillation zone; and (g) removing from the third distillation zone a light fraction stream comprising methyl acetate and acetone and a heavy fraction stream comprising methyl acetate and acetic acid.

EFFECT: invention relates to a method of producing acetic anhydride or combined production of acetic anhydride and acetic acid.

24 cl, 1 dwg, 1 ex, 1 tbl

The invention relates to a thin organic synthesis, and is intended to improve existing processes of obtaining vanillin (4-hydroxy-3-methoxybenzaldehyde) from lynnster - containing products, for example, lignosulfonates

The invention relates to the field of fine organic synthesis, and is intended to improve existing processes of obtaining vanillin (4-hydroxy-3-methoxybenzaldehyde) of the lignosulfonate

The invention relates to a method for producing a benzaldehyde - source product for production of a wide range of medicinal and aromatic substances, dyes, plant protection means

The invention relates to cyclic ketones, in particular, to an improved method for producing a square acid

FIELD: chemistry.

SUBSTANCE: terephthalic aldehyde is obtained from α,α,α',α'-tetrabromo-p-xylene while heating, followed by extraction of the end product. The method includes reacting α,α,α',α'-tetrabromo-p-xylene with O,O-dimethyl methylphosphonate at 180°C, and the end product is extracted from the reaction mass with isooctane.

EFFECT: method enables to obtain an end product with high output using a simple technique.

2 ex

FIELD: chemistry.

SUBSTANCE: invention refers to a method for alkylaromatic compound oxidation involving alkylaromatic compound oxidation for producing a first oxidation product; contacting a portion of the first oxidation product, a solvent containing ionic liquid and carboxylic acid, wherein the ionic liquid content makes more than 5 wt %, a catalytic promoter containing a bromine source, a catalyst and an oxidising agent, for producing a second oxidation product containing at least one of the following compounds: aromatic alcohol, aromatic aldehyde, aromatic ketone and aromatic carboxylic acid.

EFFECT: method enables reducing side product formation.

12 cl, 1 dwg

FIELD: chemistry.

SUBSTANCE: terephthalic aldehyde is obtained from α,α,α',α'-tetrabromo-p-xylene while heating, followed by extraction of the end product. The method includes reacting α,α,α',α'-tetrabromo-p-xylene with O,O-dimethyl methylphosphonate at 180°C, and the end product is extracted from the reaction mass with isooctane.

EFFECT: method enables to obtain an end product with high output using a simple technique.

2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a separation method intended for removing acetone from a mixture comprising acetone, methyl acetate and methyl iodide. The method includes the following steps: (a) feeding said stream comprising acetone, methyl acetate and methyl iodide into a first distillation zone; (b) feeding acetic acid into said first distillation zone, either by addition of acetic acid to said stream comprising acetone, methyl acetate and methyl iodide or by feeding acetic acid directly to the first distillation zone at one or more points at or above the point of feeding said stream comprising acetone, methyl acetate and methyl iodide into the first distillation zone at step (a), or a combination of both; (c) removing from the first distillation zone a light fraction stream comprising methyl iodide and a heavy fraction stream comprising acetone, methyl acetate, acetic acid, and a reduced amount of methyl iodide; (d) feeding into a second distillation zone the heavy fraction stream from step (c); (e) removing from the second distillation zone a light fraction stream comprising methyl acetate and methyl iodide and a heavy fraction stream comprising acetone, methyl acetate and acetic acid; (f) feeding the heavy fraction stream from step (e) into a third distillation zone; and (g) removing from the third distillation zone a light fraction stream comprising methyl acetate and acetone and a heavy fraction stream comprising methyl acetate and acetic acid.

EFFECT: invention relates to a method of producing acetic anhydride or combined production of acetic anhydride and acetic acid.

24 cl, 1 dwg, 1 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: terephthalic aldehyde is obtained from α,α,α',α'-tetrabromo-p-xylene while heating, followed by extraction of the end product. The method includes reacting α,α,α',α'-tetrabromo-p-xylene with O,O-dimethyl methylphosphonate at 180°C, and the end product is extracted from the reaction mass with isooctane.

EFFECT: method enables to obtain an end product with high output using a simple technique.

2 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of producing high-purity, halogen-free o-phthalaldehyde, having gas chromatography (GC) purity >99.5% of area, which can be used as an intermediate compound in production of paint, optical clarifying agent, in biocidal industry or photography. The disclosed method comprises the following steps: a) hydrolysis of tetrahalo-o-xylene at temperature 155-160°C and pressure 2-5 bars to o-phthalaldehyde which is b) converted in an acidic alcohol solution at temperature ranging from 0°C to boiling point with a reflux condenser to the corresponding dialkoxyphthalane and further, c) acetal is decomposed via acid hydrolysis at pH ranging from >1.5 to 7, thereby obtaining highly pure, halogen-free o-phthalaldehyde.

EFFECT: efficient method of producing high-purity, halogen-free o-phthalaldehyde.

5 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: terephthalic aldehyde is obtained from α,α,α',α'-tetrabromo-p-xylene while heating, followed by extraction of the end product. The method includes reacting α,α,α',α'-tetrabromo-p-xylene with O,O-dimethyl methylphosphonate at 180°C, and the end product is extracted from the reaction mass with isooctane.

EFFECT: method enables to obtain an end product with high output using a simple technique.

2 ex

FIELD: chemistry.

SUBSTANCE: method is to interact α,α,α',α'-tetrabrom-p-xylene with dimethyl acetal of benzaldehyde in the presence of the catalytic amount of zinc chloride at the temperature of 80°C, followed by isolation of the desired product by extraction from the reaction mixture with hot isooctane.

EFFECT: producing the desired product with high yield.

2 ex

FIELD: chemistry.

SUBSTANCE: method is to interact α,α,α',α'-tetrabrom-p-xylene with dimethyl acetal of benzaldehyde in the presence of a catalytic amount of zinc chloride at the temperature of 50°C, followed by isolation of the desired product by extraction from the reaction mixture with hot isooctane.

EFFECT: producing the desired product with high yield.

3 ex

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