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O-nitrobenzaldehyde and p-nitrobenzaldehyde and preparation method of halides thereof

A technology of p-nitrobenzaldehyde and halogenated substances, applied in the preparation of organic compounds, chemical instruments and methods, organic chemistry, etc., can solve the problems of poor product quality, serious pollution, difficult to remove, etc., and achieve stable product quality and purity Good, easy-to-control effects

Inactive Publication Date: 2009-02-11
ZHEJIANG UNIV
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Problems solved by technology

[0002] The existing methods for preparing o-, p-nitrobenzaldehyde and its halogenated products mainly include: method one (JACS, 68, 1596-1598) is to use 2-chloro-4-nitrobenzaldehyde as raw material, and the methyl group is first covered with CrO 3 -Oxidation of AcOH to diacetate followed by hydrolysis to 4-chloro-2-nitrobenzaldehyde using CrO 3 as an oxidizing agent, producing a large amount of chromium-containing wastewater, causing serious pollution; Method 2 (Chemical Reaction Engineering and Technology, 2002, 18, 1, 23-41) uses o-nitrotoluene as raw material, MnSO 4 O-nitrobenzaldehyde is obtained by catalytic oxygen oxidation, and the yield of this method is low, and the literature report has only 36%; and then hydrolyzed to obtain aromatic formaldehyde. This method has many impurities and can produce monobromine and tribromine by-products, which are difficult to remove and have poor product quality; method four (J.Org.Chem.2003, 68, 4104-4107) is Using 4-chloro-2-nitrobenzaldehyde as raw material, it reacts with N,N-dimethylformamide dimethyl acetal to convert it into N,N-dimethylstyrylamine, which is treated with NalO 4 Oxidation to 4-chloro-2-nitrobenzaldehyde, which requires the use of expensive NalO 4 As an oxidizing agent, the cost is high, and a large amount of NalO is produced at the same time 3 solid waste

Method used

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  • O-nitrobenzaldehyde and p-nitrobenzaldehyde and preparation method of halides thereof

Examples

Experimental program
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Effect test

Embodiment 1

[0026] 1) Preparation of N, N-dimethyl p-nitrostyrylamine

[0027] Add p-nitrotoluene (15.9g, 0.116mol) to N,N-dimethylformamide dimethylformal (23ml, 0.174mol) and N,N-dimethylformamide (101ml), heat to reflux , reacted for 15h, after the reaction was completed, lowered to room temperature to obtain dark red N,N-dimethyl-p-nitrostyrylamine solution, firstly recovered N,N-dimethylformamide diacetal by normal pressure distillation, and then depressurized Recover N,N-dimethylformamide by distillation, drop the raffinate to room temperature, slowly add 100ml of water, stir, and filter with suction to obtain N,N-dimethyl-p-nitrostyrylamine, which is directly used in the next step without purification reaction.

[0028] 2) preparation of p-nitrobenzaldehyde

[0029] With tetraethylammonium bromide (0.64g), the N,N-dimethyl-p-nitrostyrylamine obtained in the previous step was dissolved in a mixed solution of 200ml water and 100ml DMF, cooled with ice water, and slowly added dropwi...

Embodiment 2

[0031] 1) Preparation of N, N-dimethyl-2-chloro-4-nitrostyrylamine

[0032] 2-Chloro-4-nitrotoluene (19.9g, 0.116mol) was added to N,N-dimethylformamide dimethylformal (46ml, 0.348mol) and N,N-dimethylformamide (105.4ml ), heated to reflux for 14 hours, the reaction was completed, and cooled to room temperature to obtain a magenta N, N-dimethyl-2-chloro-4-nitrostyrylamine solution, which was first recovered by atmospheric distillation to recover N, N- Methylformamide dimethylformyl, then distilled under reduced pressure to recover N,N-dimethylformamide, the raffinate was lowered to room temperature, slowly added 100ml of water, stirred, and suction filtered to obtain purple N,N-dimethyl-2- Chloro-4-nitrostyrylamine was directly used in the next step without purification.

[0033] 2) Preparation of 2-chloro-4-nitrobenzaldehyde

[0034] Dissolve tetrabutylammonium chloride (0.5g), N, N-dimethyl-2-chloro-4-nitrostyrylamine prepared in the previous step in a mixed solution of 18...

Embodiment 3

[0036] 1) Preparation of N, N-dimethyl-2-bromo-4-nitrostyrylamine

[0037]2-Bromo-4-nitrotoluene (25.1g, 0.116mol) was added to N,N-dimethylformamide dimethylformal (30.7ml, 0.232mol) and N,N-dimethylformamide (106.4 ml), heated to reflux for 14 hours, the reaction was completed, and cooled to room temperature to obtain a purple-red N, N-dimethyl-2-bromo-4-nitrostyrylamine solution, which was first recovered by atmospheric distillation to recover N, N- Dimethyl formamide dimethyl acetal, then distilled under reduced pressure to recover N,N-dimethylformamide, the raffinate was lowered to room temperature, slowly added 100ml of water, stirred, and suction filtered to obtain purple N,N-dimethyl-2 -Bromo-4-nitrostyrylamine, without refining, is directly used in the next step reaction.

[0038] 2) Preparation of 2-bromo-4-nitrobenzaldehyde

[0039] Benzyltriethylammonium bromide (0.5g), N, N-dimethyl-2-bromo-4-nitrostyrylamine obtained in the previous step were dissolved in the m...

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Abstract

The invention discloses a preparation method for o-nitrobenzaldehyde, p-nitrobenzaldehyde and the phenylhalostannyl thereof, which comprises the following steps in sequence: toluene is used as raw material, wherein, ortho-position and para-position of toluene contain nitryl or nitryl and halogen. N,N-dialkyl formamide is used as solvent, and the raw material and the solvent are condensed with N,N-dialkyl formamide tirethylene ethanol to prepare N,N-dialkyl styrylamine, wherein, ortho-position and para-position of N,N-dialkyl styrylamine contain nitryl or nitryl and halogen; then, with the existence of phase transfer catalyst, the N,N-dialkyl styrylamine prepared is oxidized by taking peroxoic acid or hydrogen peroxide as oxidizer to produce o-nitrobenzaldehyde, p-nitrobenzaldehyde and the phenylhalostannyl thereof. By adopting the preparation method of the invention to prepare o-nitrobenzaldehyde, p-nitrobenzaldehyde and the phenylhalostannyl thereof, the operation is simple, the reaction conditions are easy to control, the raw material is easily available, the yield is higher, the product quality is stable and the purity is good.

Description

Technical field [0001] The present invention relates to the preparation method of o- and p-nitrobenzaldehyde and its halogenated products as pharmaceutical, dye and pesticide intermediates. Background technique [0002] The existing methods for preparing o- and p-nitrobenzaldehyde and their halogenated products mainly include: Method 1 (JACS, 68, 1596-1598) uses 2-chloro-4-nitrobenzaldehyde as raw material, and the methyl group is first removed by CrO 3 -AcOH is oxidized to diacetate and then hydrolyzed to 4-chloro-2-nitrobenzaldehyde. This method uses CrO 3 As an oxidant, a large amount of chromium-containing wastewater is produced, causing serious pollution; Method 2 (Chemical Reaction Engineering and Technology, 2002, 18, 1, 23-41) uses o-nitrotoluene as raw material, MnSO 4 Catalytic oxygen oxidation is used to prepare o-nitrobenzaldehyde. The yield of this method is low, with only 36% reported in the literature; method three (Can.J.Chern.Vol.33, 1955, 1819-1823) uses N...

Claims

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Application Information

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IPC IPC(8): C07C205/44C07C201/12
Inventor 戴立言俞杰王晓钟陈英奇
Owner ZHEJIANG UNIV
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