CN101928233A - Cholromethylation method of benzoic acid derivative - Google Patents
Cholromethylation method of benzoic acid derivative Download PDFInfo
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- CN101928233A CN101928233A CN2009102724863A CN200910272486A CN101928233A CN 101928233 A CN101928233 A CN 101928233A CN 2009102724863 A CN2009102724863 A CN 2009102724863A CN 200910272486 A CN200910272486 A CN 200910272486A CN 101928233 A CN101928233 A CN 101928233A
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Abstract
The invention relates to a cholromethylation method of a benzoic acid derivative, specifically comprising the step of making benzoate, benzamide, cyanobenzene and benzophenone react with paraformaldehyde and aluminium choride to generate a meta-position chloromethyl substituted benzoic acid derivative. The meta-position chloromethyl substituted benzoic acid derivative is an important intermediate for fine chemicals, pesticides and medicines.
Description
Technical field
The present invention relates to a kind of chloromethylation method of benzoic acid derivative, that is, prepare the method for 3-chloromethyl benzoic acid derivative by the chloromethylation of benzoic acid derivative.
Background technology
3-chloromethyl benzoic acid derivative all is very useful medicine intermediate, can be used for synthesizing many products.At present the synthetic method of 3-chloromethyl benzoic acid derivative series product nearly all is from m-xylene, generates the 3-tolyl acid through single oxidation, passes through monochloro generation again, generates the 3-chloromethyl benzoic acid, and then prepares these derivatives.Yet the selectivity in above-mentioned single oxidation and monochloro generation is all bad, finally causes 3-chloromethyl benzoic acid derivative production process more complicated, and cost is higher.
U.S. Pat 4562280 discloses the method for the chloromethylation that contains an alkyl (activating group) and an electron-withdrawing group (group deactivates) aromatic hydrocarbon simultaneously.Mentioned again in this patent and reported that aromatic acid or its ester can be in the vitriol oils and chloromethyl methyl ether generation chloromethylation, but do not had reference, whether had activating group also unknown on the ring of aromatic acid or its ester.
We attempted adopting the method for US4562280 to carry out the chloromethylation of benzoic acid derivative, and the result ends in failure.
Also have document to say that aromatic acid or its ester can be in chlorsulfonic acids and Paraformaldehyde 96 generation chloromethylation, but yield is all very low, and does not have example.Moreover chloromethyl methyl ether is strong carcinogens, and large-scale application personnel health has a big risk.Chlorsulfonic acid reactive behavior height is easy to take place side reactions such as sulfonation and chlorosulphonation in addition.
Up to the present do not find the report of the chloromethylation of cyanobenzene.
Theoretically, the chloromethylation of benzoic acid derivative is the simplest and the clearest preparation method of 3-chloromethyl benzoic acid derivative.Yet benzoic acid derivative belongs to the aromatic hydrocarbons that contains the group that deactivates, and chloromethylation be difficult to take place under the usual conditions, even if perhaps take place, yield is also very poor, therefore the more simple and clear Cholromethylation method efficiently of very necessary exploitation.
The last chloromethylation of phenyl ring (aromatic ring) is a common reactant, and can last substituent the pushing away of phenyl ring (aromatic ring)/draw the power of electronic action carry out reacting, selectivity, yield, transformation efficiency etc. have decisive influence.Different phenyl ring (aromatic ring) structure may need different reaction conditionss, i.e. Zui You reaction conditions difference, the place that this needs people to study just.
The benzoic acid derivative of this piece of patent requirement is owing to exist ester group (carbalkoxy), amide group (amido carbonyl), ketone carbonyl, cyano group on the phenyl ring, and these all have intensive to draw electronic action, reaction under the conventional blanc chloromethylation condition.On basic organic chemistry book or with these derivatives, be summarized in the material category that can not carry out chloromethylation, perhaps avoid and not talking.
Torpescence phenyl ring (aromatic ring) is gone up chloromethylation and usually can't or be difficult to carry out, and Just because of this, methodology, Study on Process that torpescence phenyl ring (aromatic ring) is gone up chloromethylation get not deeply.We are owing to need intermediate such as 3-chloromethyl benzoic acid methyl esters, but long according to the general method reactions steps, cost is high, have therefore just studied torpescence phenyl ring (aromatic ring) in great detail and have gone up chloromethylation.
Summary of the invention
The objective of the invention is to overcome deficiency of the prior art, the Cholromethylation method of the benzoic acid derivative that a kind of reaction is gentle more, yield is higher, have higher conversion is provided.
Benzoic acid derivative of the present invention comprises PhCOOR (benzoic ester class), PhCONR
1R
2(benzoic amides), PhCN (cyanobenzene) and PhCOPh (benzophenone).
When test found that R is secondary alkyl and tertiary alkyl among the PhCOOR, Cholromethylation method of the present invention was inapplicable, and tracing it to its cause may be that removal of alkylation reaction has taken place.Cholromethylation method of the present invention in addition is also inapplicable for benzamide (R1 and R2 are H among the PhCONR1R2).
Test shows, solvent to of the present invention influence bigger, when using some solvent, reaction even can not carry out.Chloromethylation of the present invention is to carry out in the organic solvent of relative inertness.The solvent that is suitable for comprises hydrochloric ether, sherwood oil, dithiocarbonic anhydride, and solvent is methylene dichloride and chloroform preferably, and only solvent is a chloroform.
The material proportion of chloromethylation of the present invention is counted with mole: benzoic acid derivative: Paraformaldehyde 96: aluminum chloride 1: 0.5-1: 1.5-2.Can improve transformation efficiency though increase Paraformaldehyde 96 and aluminum chloride proportioning, the amplitude that side reaction increases is bigger, and by product is not easily separated, and therefore, material ratio is very important for controlling suitable transformation efficiency.
The optimal temperature scope of chloromethylation of the present invention is at 20-65 ℃, reaction times 5-15 hour.
The feeding sequence of chloromethylation of the present invention is little to the reaction influence.
Embodiment
Benzoic acid derivative and Paraformaldehyde 96 and aluminum chloride shown in the formula (I) carry out chloromethyl reaction in solvent, shown in the production (II) between the benzoic acid derivative of position chloromethylation, reaction equation is as follows:
Formula (I) formula (II)
In formula (I) and formula (II), A=CN, COOR, CONR
1R
2Or PhCO.
The solvent that reaction is used in the said process is selected from wherein a kind of of methylene dichloride, trichloromethane, tetrachloromethane, sherwood oil or dithiocarbonic anhydride.Reacting material ratio is counted with mole: benzoic acid derivative: Paraformaldehyde 96: aluminum chloride is 1: 0.5-1: 1.5-2, the temperature range of reaction is 20-65 ℃, reaction times 5-15 hour.When A=COOR, R is selected from the C1-C8 primary alkyl.Work as A=CONR
1R
2The time, R
1And R
2Be respectively H, C1-C12 alkyl, but R
1And R
2Can not be H simultaneously.
Further specify the present invention with embodiment below.
Embodiment 1: the chloromethylation of methyl benzoate
In the 100ml there-necked flask, add the 50ml methylene dichloride, 26 gram (0.19mol) aluminum chlorides and 3.0 gram (0.1mol) Paraformaldehyde 96s, stir and drip 13.6 gram (0.1mol) methyl benzoate down, back flow reaction is 10 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 20ml dichloromethane extraction, merge organic layer, 10ml water washing twice concentrates and reclaims methylene dichloride, resistates 16.5 grams, HPLC analyzes, wherein contain 3-chloromethyl benzoic acid methyl esters 80%, unreacted methyl benzoate 5%, other impurity 15%.
Embodiment 2: the chloromethylation of methyl benzoate
In the 100ml there-necked flask, add the 50ml trichloromethane, 26.5 gram (0.2mol) aluminum chloride and 1.5 gram (0.05mol) Paraformaldehyde 96s, stirring is cooled to below 10 ℃, drip 13.6 gram (0.1mol) methyl benzoate, 50 ℃ were reacted 8 hours then, and reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 20ml chloroform extraction, merges organic layer, twice of 10ml water washing, concentrate and reclaim trichloromethane, resistates 15.2 grams, HPLC analyzes, and wherein contains 3-chloromethyl benzoic acid methyl esters 50%, unreacted methyl benzoate 35%, other impurity 15%.
Embodiment 3: the chloromethylation of cyanobenzene
In the 100ml there-necked flask, add the 50ml chloroform, 25 gram (0.189mol) aluminum chlorides and 2.8 gram (0.093mol) Paraformaldehyde 96s, stir and add 10 gram (0.097mol) cyanobenzenes down, back flow reaction is 15 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 54ml chloroform extraction, merge organic layer, 10ml water washing twice concentrates and reclaims chloroform, resistates 14.5 grams, HPLC analyzes, wherein contain 3-chloromethylbenzene formonitrile HCN 73%, unreacted cyanobenzene 17.2%, other impurity 9.8%.
Embodiment 4: the chloromethylation of cyanobenzene
In the 100ml there-necked flask, add the 50ml chloroform, 20 gram (0.15mol) aluminum chlorides and 2.8 gram (0.093mol) Paraformaldehyde 96s, stir and add 10 gram (0.097mol) cyanobenzenes down, back flow reaction is 12 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 54ml chloroform extraction, merge organic layer, 10ml water washing twice concentrates and reclaims chloroform, resistates 14.5 grams, HPLC analyzes, wherein contain 3-chloromethylbenzene formonitrile HCN 68%, unreacted cyanobenzene 25%, other impurity 7%.
Embodiment 5: the chloromethylation of benzophenone
In the 100ml there-necked flask, add the 50ml chloroform, 25 gram (0.189mol) aluminum chlorides and 3.0 gram (0.1mol) Paraformaldehyde 96s, stir and add 18 gram (0.099mol) benzophenone down, 30 ℃ were reacted 12 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 60ml chloroform extraction, merge organic layer, 10ml water washing twice concentrates and reclaims chloroform, resistates 22 grams, HPLC analyzes, wherein contain 3-chloromethyl benzophenone 83.5%, unreacted benzophenone 14%, other impurity 2.5%.
Embodiment 6: the chloromethylation of benzophenone
In the 100ml there-necked flask, add the 50ml methylene dichloride, 25 gram (0.189mol) aluminum chlorides and 3.0 gram (0.1mol) Paraformaldehyde 96s, stir and add 18 gram (0.099mol) benzophenone down, 25 ℃ were reacted 15 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 60ml dichloromethane extraction, merge organic layer, 10ml water washing twice concentrates and reclaims methylene dichloride, resistates 22 grams, HPLC analyzes, wherein contain 3-chloromethyl benzophenone 78.3%, unreacted benzophenone 19%, other impurity 2.7%.
Embodiment 7:N, the chloromethylation of N-dimethyl benzamide
In the 100ml there-necked flask, add the 50ml chloroform, 20 gram (0.15mol) aluminum chlorides and 2.9 gram (0.097mol) Paraformaldehyde 96s, stir 15 gram (0.1mol) N of adding down, the N-dimethyl benzamide, 50 ℃ were reacted 10 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 60ml chloroform extraction, merge organic layer, 10ml water washing twice concentrates and reclaims chloroform, resistates 19.5 grams, HPLC analyzes, wherein contain N, N-dimethyl 3-chloromethylbenzene methane amide 89.6%, unreacted N, N-dimethyl benzamide 4.3%, other impurity 6.1%.
Embodiment 8:N, the chloromethylation of N-dimethyl benzamide
In the 100ml there-necked flask, add the 50ml chloroform, 26.5 gram (0.2mol) aluminum chloride and 3.0 gram (0.1mol) Paraformaldehyde 96s, stir 15 gram (0.1mol) N of adding down, the N-dimethyl benzamide, 45 ℃ were reacted 12 hours then, reactant flow is added in the 100 gram frozen water, stirred 30 minutes, layering, water layer adds the 60ml chloroform extraction, merge organic layer, 10ml water washing twice concentrates and reclaims chloroform, resistates 19 grams, HPLC analyzes, wherein contain N, N-dimethyl 3-chloromethylbenzene methane amide 85%, unreacted N, N-dimethyl benzamide 11%, other impurity 4%.
Above-mentioned reaction product can be passed through such as method purifying such as essence slide, crystallization, recrystallization and column chromatographies.
Attached structural confirmation research:
1) 3-chloromethyl benzoic acid methyl esters structural confirmation research
Methyl benzoate chloromethylation products after an amount of rectification and purification and water are mixed, add an amount of phase-transfer catalyst Morpan BB, add an amount of potassium permanganate oxidation, filter, water adds S-WAT and removes excessive potassium permanganate, refilter, acidifying, filter and collect white solid, drying is surveyed 341-342 ℃ of its fusing point, conforms to m-phthalic acid document fusing point, its IR spectrogram (Fig. 2) conforms to m-phthalic acid reference substance (Fig. 1), thereby the anti-structural formula that pushes away affirmation methyl benzoate chloromethylation products is a 3-chloromethyl benzoic acid methyl esters.The reaction principle of structural confirmation is as follows:
2) 3-chloromethylbenzene formonitrile HCN structural confirmation research
Cyanobenzene chloromethylation products after an amount of rectification and purification and water are mixed, add an amount of phase-transfer catalyst Morpan BB, add an amount of potassium permanganate oxidation, filter, water adds S-WAT and removes excessive potassium permanganate, refilter, refluxed 2 hours after adding an amount of sodium hydroxide, acidifying is filtered and is collected white solid, drying, survey 341.5-342.6 ℃ of its fusing point, conform to m-phthalic acid document fusing point, its IR spectrogram (Fig. 3) conforms to m-phthalic acid reference substance (Fig. 1), thereby the anti-structural formula that pushes away affirmation cyanobenzene chloromethylation products is a 3-chloromethylbenzene formonitrile HCN.The reaction principle of structural confirmation is as follows:
3) 3-chloromethyl benzophenone structural is confirmed research
Benzophenone chloromethylation products after an amount of rectification and purification and water are mixed; add an amount of phase-transfer catalyst Morpan BB; add an amount of potassium permanganate oxidation; filter; water adds S-WAT and removes excessive potassium permanganate; refilter; acidifying; filter and collect white solid; drying is surveyed 164.5-165.5 ℃ of its fusing point, conforms to 3-benzoyl phenylformic acid document fusing point; its IR spectrogram (Fig. 5) is consistent with 3-benzoyl phenylformic acid reference substance (Fig. 6), thereby the anti-structural formula that pushes away affirmation benzophenone chloromethylation products is a 3-chloromethyl benzophenone.
Reference substance 3-benzoyl phenylformic acid preparation: the 3-cyanogen methyldiphenyl ketone and the water of an amount of outsourcing are mixed; add an amount of phase-transfer catalyst Morpan BB; add an amount of potassium permanganate oxidation, filter, water adds S-WAT and removes excessive potassium permanganate; refilter; acidifying is filtered and is collected white solid, drying; obtain reference substance 3-benzoyl phenylformic acid, Fig. 6 is its IR spectrogram.
The reaction principle of structural confirmation is as follows:
4) N, the research of N-dimethyl 3-chloromethylbenzene methane amide structural confirmation
With the N after an amount of rectification and purification, N-dimethyl benzamide chloromethylation products and water mix, add an amount of potassium permanganate oxidation, filter, water adds S-WAT and removes excessive potassium permanganate, refilter, add behind an amount of sodium hydroxide and refluxed acidifying 2 hours, filter and collect white solid, drying is surveyed 341.5-342.8 ℃ of its fusing point, conforms to m-phthalic acid document fusing point, its IR spectrogram (Fig. 4) conforms to m-phthalic acid reference substance (Fig. 1), thereby counter pushing away confirmed N, and the structural formula of N-dimethyl benzamide chloromethylation products is N, N-dimethyl 3-chloromethylbenzene methane amide.The reaction principle of structural confirmation is as follows:
The IR spectrogram that spectrogram 1～Fig. 6 does for structural confirmation institute.
Claims (5)
1. the Cholromethylation method of a benzoic acid derivative, it is characterized in that will be shown in reaction formula Chinese style (I) benzoic acid derivative and Paraformaldehyde 96 and aluminum chloride in solvent, carry out the chloromethyl reaction, the benzoic acid derivative of position chloromethylation between shown in the production (II), reaction equation is as follows:
In formula (I) and formula (II), A=CN, COOR, CONR
1R
2Or PhCO.
2. method according to claim 1, the solvent that it is characterized in that reacting use are selected from wherein a kind of of methylene dichloride, trichloromethane, tetrachloromethane, sherwood oil or dithiocarbonic anhydride.
3. method according to claim 1, it is characterized in that reacting material ratio counts with mole: benzoic acid derivative: Paraformaldehyde 96: aluminum chloride is 1: 0.5-1: 1.5-2, the temperature range of reaction is 20-65 ℃, reaction times 5-15 hour.
4. method according to claim 1 is characterized in that when A=COOR, R is selected from the C1-C8 primary alkyl.
5. method according to claim 1 is characterized in that working as A=CONR
1R
2The time, R
1And R
2Be respectively H, C1-C12 alkyl, but R
1And R
2Can not be H simultaneously.
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| CN105384625A (en) * | 2015-12-17 | 2016-03-09 | 湖北相和精密化学有限公司 | 3-chloro methyl benzoyl chloride synthetic method |
| CN105384620B (en) * | 2015-12-17 | 2017-07-28 | 湖北相和精密化学有限公司 | A kind of synthetic method of 3 chloromethyl benzoic acid |
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| CN114907234A (en) * | 2022-05-07 | 2022-08-16 | 南京杰运医药科技有限公司 | Preparation method of 2-fluoro-5-formylbenzonitrile |
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