CN103936567B - Co-production method of preparing corresponding alcohol, ester, aldehyde and acid by oxidizing p-methoxyl methylbenzene by oxygen - Google Patents
Co-production method of preparing corresponding alcohol, ester, aldehyde and acid by oxidizing p-methoxyl methylbenzene by oxygen Download PDFInfo
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- C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
- C07C41/01—Preparation of ethers
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- C07C45/32—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen
- C07C45/33—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties
- C07C45/34—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by oxidation with molecular oxygen of CHx-moieties in unsaturated compounds
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- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
- C07C51/255—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting
- C07C51/265—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting having alkyl side chains which are oxidised to carboxyl groups
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Abstract
The invention relates to a co-production method for preparing corresponding alcohol, ester, aldehyde and acid by oxidizing p-methoxyl methylbenzene by oxygen. The method comprises the following steps: adding p-methoxyl methylbenzene, a catalyst I and a solvent into an oxidizing reaction kettle, and introducing oxygen to react; after oxidizing reaction, recovering the solvent and optionally selecting to apply mechanically, and then adding water to wash the catalyst I to obtain an organic phase I and an aqueous phase I; adding alkali into the organic phase I, decompressing and evaporating an organic phase II, after adding water to the bottom, adjusting the pH value by an acid, and filtering to obtain p-methoxybenzoic acid; distilling the water phase I to recover water, optionally selecting to apply mechanically, further adding the catalyst I and the solvent at the bottom, and optionally selecting to apply mechanically in oxidizing reaction; rectifying the organic phase II to obtain a product p-methoxybenzaldehyde and anisyl acetate; carrying out basic hydrolysis on anisyl acetate to obtain an anisic alcohol crude product; and rectifying to obtain an anisic alcohol pure product. The co-production method provided by the invention has the advantages of greenness and environment protection, mild reaction condition, low cost and less three waste, and is easy to industrially produce, and the obtained product is widely applied to the fields of foods, medicines and daily chemicals.
Description
Technical field
The present invention relates to a kind of preparation method of organic intermediate, in particular to the co-production preparation method of p-methoxybenzyl alcohol, cassie ketone, aubepine and anisic acid, belong to daily-use chemical industry technical field.
Background technology
Aubepine (Anisic aldehyde), is colourless to weak yellow liquid under normal temperature, has the smell of similar hawthorn.Density 1.123g/cm
3(20 DEG C).Fusing point 0 DEG C.Boiling point 249.5 DEG C.Specific refractory power 1.5731.Be insoluble in water, be soluble in ethanol, ether, acetone, chloroform.Can volatilize with water vapour.Be present in olium anisi, Sweet fennel oil, oleum anethi, acacia flos, vanilla medicinal extract at occurring in nature, obtain through oxidation separation and Extraction.As spices, preparation bouquet type composition, for food and makeup, perfumed soap etc.Pharmaceutically be used as the intermediate of antihistamine drug, as little being also used as such as antibiotic oxyammonia benzylpenicillin processed electroplate optical brightener etc.
The synthetic method of aubepine comprises following several:
(1) methylated by phenol methyl-sulfate, and then through the obtained (PCT2008023836 of the reaction such as chloromethylation, hydrolysis; CN01838173; Compt.Rend., 1934,198:2256-22588);
(2) by p-methyl phenol through methylating, reoxidize and obtain (CN1249362; Russ., 2043986; JP2011162489; CN1491930; JP2010202556; EP459729; Bull.Chem.Soc.Japan, 1988,61 (3): 967-971; EP228275; JP62108837; JP60233027; J.Mole.Catal., 1990,61 (1): 51-54; J.Org.Chem., 1997,62 (20): 6810-6813; JP102070382);
(3) methylated by p-Hydroxybenzaldehyde and obtain (Org.Process Res.Dev., 2005,9 (1): 70-79; PCT2001009072; Chem.Res.Chin.Universities, 2013,29 (2): 319-323; JP10287608; CN102531860; CN101462933; NA9200968; CN1319581; JP63104937; CN1249298; CN1247851; Adv.Synth.Catal., 2004,346 (6): 633-638; EP577476).
P-methoxybenzyl alcohol, colourless or micro-yellow liquid.Fusing point 23-25.5 DEG C, boiling point 159 DEG C, relative density 1.113 (15/15 DEG C), refractive index 1.5442.Be soluble in alcohol and ether, water-soluble hardly.There is slightly sweetish fennel fragrance, be usually used in essence such as preparation jasmine, Syringa oblata Lindl. etc., be suitable for allocating perfume.This Pin Shi China GB2760-86 is defined as the flavouring agent allowing to use.Main in order to prepare the essence such as vanilla, chocolate, cocoa, almond, peach.Also for organic synthesis with as solvent.
Synthesis p-methoxybenzyl alcohol method primarily of aubepine through reducing obtained (CN102320939; J.Ind.Eng.Chem., 2007,13 (7): 1067-1075; J.Med.Chem., 2013,56 (20): 8201-8205; Angew.Chem.-Int.Edit., 2013,52 (45): 11871-11874; Angew.Chem.-Int.Edit., 2013,52 (19): 5120-5124; Organometallics, 2013,32 (16): 4501-4506; Chem.Commun., 2012,48 (66): 8276-8278; Angew.Chem.-Int.Edit., 2012,51 (48): 12102-12106; Catal.Lett., 2013,143 (1): 122-125; J.Mole.Catal.A:Chem., 2009,299 (1-2): 98-101; Eur.J. Org.Chem., 2009, (21): 3567-3572; Tetrahedron Lett., 2009,50 (32): 4624-4628; CN1994988; Tetrahedron Lett., 2006,47 (25): 4161-4165; PCT2003089395; Synth.Commun., 2001,31 (17): 2719-2725; Catal.Commun., 2012,28:147-151; Green Chem., 2012,14 (5): 1372-1375; J.Am.Chem.Soc., 2010,132 (34): 11978-11987; ACS Catal., 2013,3 (2): 182-185; Tetrahedron Lett., 2012,53 (2): 148-150; Daily chemical industry, 2008,38 (4): 242-244; JP2006088026).
Anisic acid, colourless acicular crystal, fusing point 182-185 DEG C (lit.), boiling point 275 DEG C, density 1.385, specific refractory power 1.571-1.576, flash-point 185 DEG C.Be dissolved in ethanol, ether, chloroform, be slightly soluble in hot water, be insoluble in cold water.As medicine intermediates such as eggplant La Xitan, ethamine sulphur skin ketone, also can be used for spices, sanitas etc.Can be raw material by P-hydroxybenzoic acid, react with methyl-sulfate and obtain (Indian Pat.Appl., 2008MU01043; Indian Pat.Appl., 2006MU00718; ), can aubepine be also raw material, through oxidation preparation (Tetrahedron Lett., 2013,54 (46): 6222-6225; Synlett, 2013,24 (8): 963-966; Inorg.Chem., 2008,47 (13): 5821-5830; Indian Pat.Appl., 1999DE01492; PCT2011037542; PCT2004054956).
Acetic acid fennel ester, Anisyl acetate, density 1.014 (20 DEG C), boiling point 270 DEG C, specific refractory power 1.5110 ~ 1.5160.Colourless to light yellow liquid, there are stronger Acacia fragrance and cassia bark fragrance, pleasantly sweet.Water insoluble, propylene glycol, glycerine, be dissolved in ethanol and most of non-volatile oils.The bouquet type compositions such as modulation cloves, silvery white Acacia, Acacia, violet, for makeup; The flavor essences such as modulation chocolate, cocoa, vanilla, berry, strawberry, for food.With anisy alcohol and acetic acid (acetic anhydride) for raw material, direct esterification obtains (J.Flow Chem., 2012,2:47-51; Synthesis, 2011, (10): 1621-1625; J.Iran.Chem.Soc., 2009,6 (3): 523-532; Tetrahedron Lett., 2009,50 (4): 395-397; Catal.Commun., 2014,44:24-28; PCT2002038553).
Obviously, synthesis p-methoxybenzyl alcohol, anisic acid and acetic acid fennel ester need take all aubepine as raw material, or through reduction, or through oxidation, or through esterification preparation, reaction process and aftertreatment are all loaded down with trivial details.And aubepine, main at present take p-cresol as raw material, in alkaline medium, is prepared into p-Hydroxybenzaldehyde through dioxygen oxidation, obtains via methyl-sulfate etherificate.No matter be oxidation, or etherificate, all need to produce a large amount of three wastes, bring pressure to environmental protection and production.
Summary of the invention
The object of the present invention is to provide one can prepare high-quality p-methoxybenzyl alcohol simultaneously, cassie ketone, the co-production of aubepine and anisic acid, use initiator is avoided in the oxidizing reaction stage, especially halogen initiator, use cheap oxygen as oxygenant, avoid and use chemical oxidizing agent and other organic peroxide oxidant, adopt gentle alkaline hydrolysis conditions, adopt the circulation realizing material from closed loop, because this reducing the generation of manufacturing cost and the three wastes, alleviate environmental protection pressure, but also have easy, be easy to the feature of control and suitability for industrialized production.
The present inventor is found by research, by the synthesis technique comprised the steps, with to methoxy toluene for raw material, under the existence of Halogen catalyzer, p-methoxybenzyl alcohol, cassie ketone, aubepine and anisic acid is generated through dioxygen oxidation, can obtain the p-methoxybenzyl alcohol of high-quality, cassie ketone, aubepine and anisic acid, reactive chemistry formula is:
Therefore, dioxygen oxidation of the present invention comprises the following steps the co-production that methoxy toluene prepares corresponding p-methoxybenzyl alcohol, cassie ketone, aubepine and anisic acid:
Step 1), add in oxidizing reactor methoxy toluene, catalyst I and solvent, pass into oxygen at a certain temperature, stopped reaction after reaction certain hour;
Step 2), oxidizing reaction terminates, recycling design, optionally for applying mechanically, then adding washing and going catalyst I, obtain organic phase I and aqueous phase I;
Step 3), in organic phase I, add alkali, decompression steam organic phase II, heat up in a steamer the end add water after use sour adjust pH, filter obtain anisic acid;
Step 4), aqueous phase I Distillation recovery water, optionally for applying mechanically, heating up in a steamer after the end adds catalyst I and solvent, optionally applying mechanically for oxidizing reaction;
Step 5), organic phase II rectifying obtains finished product aubepine and cassie ketone;
Step 6), cassie ketone alkaline hydrolysis, obtains anisy alcohol crude product, obtains anisy alcohol sterling through rectifying.
The following specifically describes the present invention.
In step 1 of the present invention, add in oxidizing reactor methoxy toluene, catalyst I and solvent, pass into oxygen at a certain temperature, stopped reaction after reaction certain hour.
According to the present invention, the solvent used in step 1 is organic carboxyl acid class, and as formic acid, acetic acid, propionic acid, butyric acid, Mono Chloro Acetic Acid, trifluoroacetic acid etc., preferred acetic acid or propionic acid, particularly preferably acetic acid is the solvent of oxidizing reaction.
Solvent for use (such as acetic acid) be 1 ~ 50:1, preferably 3 ~ 30:1, more preferably 5 ~ 15:1 to the mole dosage ratio of methoxy toluene.
Used catalyst I is transition metal salt, preferred acetate, as cobaltous acetate, manganous acetate, nickelous acetate, cerous acetate, chromium acetate, zinc acetate, ironic acetate, crystal aerugo, Jing Ti/Bao Pian COBALT NITRATE CRYSTALS/FLAKES, manganous nitrate, nitric acid ketone, cobalt chloride, cobaltous bromide, acetylacetone cobalt, ferric acetyl acetonade, cobalt stearate, manganese stearate, cobalt naphthenate, acid chloride, one of Palladous chloride etc., or the composite catalyst of certain mol proportion composition pressed by several catalyzer wherein, preferred cobaltous acetate, manganous acetate, chromium acetate, cerous acetate, acid chloride, ironic acetate, one of venus crystals etc., or they press the composite catalyst of certain mol proportion composition.
According to the present invention, select transition metal salt as the catalyzer of oxidizing reaction, can avoid using initiator, especially not use halogen initiator, make not contain micro-initiator in the finished product p-methoxybenzyl alcohol, the safety requirements of food, medicine and other fields can be met completely.
Used catalyst I be 0.1 ~ 2.0:1 to the mole dosage ratio of methoxy toluene, preferably 0.2 ~ 1.0.
The temperature of oxidizing reaction is 40 ~ 150 DEG C, and preferable reaction temperature is 80 ~ 120 DEG C, more preferably 100 ~ 115 DEG C.
Oxidation pressure (gauge pressure) is 0 ~ 2.0MPa, preferably 0 ~ 1.2MPa, more preferably 0 ~ 0.5MPa, wherein, carries out oxidizing reaction at ambient pressure when gauge pressure is 0.
Oxidation time is 0.1-20h, preferred 1-10h, more preferably 2-8h.
By step 1 of the present invention, use cheap oxygen as oxygenant, to methoxy toluene catalyzed oxidation in liquid phase situation, avoid using chemical oxidizing agent and other organic peroxide oxidant, mainly generate aubepine, acetic acid fennel ester and a small amount of anisic acid.
In step 2 of the present invention, oxidizing reaction terminates, recycling design, optionally for applying mechanically, then adding washing and going catalyst I, obtain organic phase I and aqueous phase I.
According to the present invention, preferably need to control certain moisture from oxidizing reaction system recovered solvent such as acetic acid and just can apply mechanically, such as, control the moisture of acetic acid 0 ~ 50%, preferably control the moisture of acetic acid 3 ~ 30%.
After solvent recuperation terminates, need to add water and catalyst I is carried out washing separation, obtain organic phase I and aqueous phase I respectively.
Washing times can be 1 ~ 10 time, and preferred washing times is 2 ~ 6 times, more preferably 3 ~ 5 times.
During each washing water be 0.1 ~ 40:1, preferably 1 ~ 20:1 to the mole dosage ratio of methoxy toluene, more preferably 3 ~ 5 times.
In step 3 of the present invention, in organic phase I, add alkali, decompression steam organic phase II, heat up in a steamer the end add water after use sour adjust pH, filter obtain anisic acid.
The alkali that step 3 of the present invention uses is basic metal inorganic acid salt or oxyhydroxide, is preferably sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide etc., more preferably sodium carbonate and salt of wormwood, particularly preferably sodium carbonate.
Described alkali adds in solid form, alkali be 0.01 ~ 1:1, preferably 0.05 ~ 0.5:1, more preferably 0.1 ~ 0.3:1 to the mole dosage ratio of methoxy toluene.
Decompression steams organic phase II, heats up in a steamer the end to add with acid for adjusting pH value after water, can adjust ph=1-5, preferred 2-3.Acid used is mineral acid example hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid etc., or organic acid is as formic acid, acetic acid, propionic acid, butyric acid etc., preferably sulfuric acid and acetic acid, particularly preferably sulfuric acid.
For sulfuric acid, its concentration is 5-85%, is preferably 72%; Temperature of reaction is 60 ~ 120 DEG C, preferably 80 ~ 110 DEG C.
In step 4 of the present invention, aqueous phase I Distillation recovery water, optionally for applying mechanically, heating up in a steamer after the end adds catalyst I and solvent, optionally applying mechanically for oxidizing reaction.
Aqueous phase I Distillation recovery water, without the need to any process, can be directly used in step 2 washing and to apply mechanically, and heats up in a steamer after the end adds appropriate catalyst I and solvent, is preferably directly used in oxidizing reaction and applies mechanically.
The above-mentioned amount adding catalyzer be catalyzer first charging capacity 1 ~ 30%, preferably 1 ~ 10%.
Charging capacity is identical first with acetic acid to add the amount of solvent acetic acid.
In step 5 of the present invention, organic phase II rectifying obtains finished product aubepine and cassie ketone.
Such as, at still temperature 124-130 DEG C and under pressure 3-5mmHg, carry out rectifying obtain aubepine, at still temperature 136-138 DEG C He under pressure 3-5mmHg, carry out rectifying, obtain cassie ketone.
In step 6 of the present invention, cassie ketone alkaline hydrolysis, obtains anisy alcohol crude product, obtains anisy alcohol sterling through rectifying.
Alkaline hydrolysis alkali used is the aqueous solution of an alkali metal salt or oxyhydroxide, the aqueous solution of preferred sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide etc., the aqueous solution of preferred sodium hydroxide, potassium hydroxide etc.
Described paper mill wastewater is 1 ~ 50%, preferably 5 ~ 30%.
Described alkali be 1 ~ 5:1, preferably 1.2 ~ 3:1, more preferably 1.5 ~ 2:1 to the mole dosage ratio of methoxy toluene.
Temperature of reaction is 60 ~ 120 DEG C, preferably 80 ~ 110 DEG C.
Reaction times is 0.5 ~ 5h, preferably 1.5 ~ 3.0h.
Then, the anisy alcohol crude product that hydrolysis reaction obtains such as carries out rectifying with pressure 3-5mmHg at still temperature 130-136 DEG C, obtains final product anisy alcohol.
Beneficial effect of the present invention is mainly reflected in the following aspects:
(1), the oxidizing reaction stage, select transition metal salt as the catalyzer of oxidizing reaction, avoid the use of initiator, particular avoid the use of halogen initiator, for the p-methoxybenzyl alcohol of production high-quality simultaneously, cassie ketone, aubepine and anisic acid provide a kind of good method, obtained product can be used for the fields such as food, medicine, detergents and cosmetic.
(2), oxidizing reaction uses cheap oxygen as oxygenant, avoids the use of chemical oxidizing agent and other organic peroxide oxidant, has the feature of economy, environmental protection, green high-efficient.
(3), provide a kind of convenient method reclaiming catalyzer, and the catalyzer reclaimed is applied mechanically repeatedly, does not find decay of activity.
(4), adopt gentle alkaline hydrolysis conditions, namely cassie ketone can easily be changed into p-methoxybenzyl alcohol, reduce manufacturing cost.
(5), adopt self-closing circulation technology, achieve the circulation of all materials, greatly reduce the generation of manufacturing cost and the three wastes, alleviate environmental protection pressure.
The inventive method also has easy, to be easy to control and suitability for industrialized production feature.
Embodiment
Further explain and describe content of the present invention below by way of embodiment, but embodiment is not to be construed as limiting the scope of the invention.
embodiment 1
488.8Kg acetic acid (KF<1%), 25.2Kg cobaltous acetate, 12.5Kg manganous acetate and 122.2Kg are put in dry stainless steel oxidation still to methoxy toluene, after being warmed up to 105-115 DEG C, pass into oxygen, stop passing into oxygen after pressure (gauge pressure) is for insulation reaction 6.5h under 0.10MPa, sampling is GC and HPLC and is detected, GC result is, aldehydic acid is detected to methoxy toluene 51.5699%, aubepine 25.9841%, p-methoxybenzyl alcohol 1.1660% and acetic acid fennel ester 20.5117%, HPLC and compares 13.2:1.
Oxidizing reaction terminates, and reclaims acetic acid KF=5.42%, acetic acid content 89.29%, is directly used in down batch oxidizing reaction and applies mechanically.Acetic acid reclaims and terminates, and under nitrogen protection, respectively with the clean tap water washing of 200Kg, 100Kg and 50Kg, stratification after stirring 30min, obtains aqueous phase I399.3Kg and oil phase I150.5Kg.Get oil phase and do GC and HPLC detection, GC result is, detects aldehydic acid compare 13.5:1 to methoxy toluene 51.5072%, aubepine 25.8914%, p-methoxybenzyl alcohol 0.9629% and acetic acid fennel ester 20.9071%, HPLC.
Under nitrogen protection, add in still kettle by the oil phase I150.5Kg of washing gained, add anhydrous sodium carbonate 5Kg, underpressure distillation obtains organic phase II137Kg.Heating up in a steamer the end adds 100Kg water, is neutralized to pH=2-3 with 72% sulfuric acid, filters, obtains anisic acid 4.5Kg.
Organic phase II137Kg rectifying under still temperature 110-124 DEG C and 6-8mmHg pressure obtains methoxy toluene 57.9Kg, GC purity 99.87%, under still temperature 124-130 DEG C and 3-5mmHg pressure, rectifying obtains aubepine 33.7Kg, GC purity 99.27%, cassie ketone 35.1Kg is obtained, GC purity 99.93% with rectifying under still temperature 136-138 DEG C and 3-5mmHg pressure.
Proceed in still kettle by aqueous phase I405.4Kg, open and stir, normal pressure, is warming up to 100-121 DEG C, and recycle-water 352Kg is used for applying mechanically, and heats up in a steamer end catalyst I and applies mechanically for oxidizing reaction.
192Kg water and 48Kg sodium hydroxide are put in hydrolytic reaction pot, 65-75 DEG C is warmed up to after dissolving, cassie ketone 35.1Kg is dripped in 30min, drip off rear insulation 1.5-2h, after reaction terminates, stratification, obtains aqueous phase II248.1Kg and p-methoxybenzyl alcohol crude product 28.1Kg, GC purity 99.19%.Then under still temperature 130-136 DEG C and 3-5mmHg pressure, carry out rectifying, obtain finished product p-methoxybenzyl alcohol 25.6Kg, GC purity 99.85%.
embodiment 2
488.8Kg acetic acid (KF<1%), 25.6Kg cobaltous acetate, 19.9Kg cerous acetate and 122.2Kg are put in dry stainless steel oxidation still to methoxy toluene, after being warmed up to 105-115 DEG C, pass into oxygen, stop after insulation reaction 5.0h passing into oxygen under pressure is normal pressure (namely gauge pressure is 0MPa), sampling is GC and HPLC and is detected, GC result is, aldehydic acid is detected to methoxy toluene 54.4636%, aubepine 15.2655%, p-methoxybenzyl alcohol 0.6895% and acetic acid fennel ester 27.8973%, HPLC and compares 39.4:1.
Oxidizing reaction terminates, and reclaims acetic acid KF=5.24%, acetic acid content 88.89%, is directly used in down batch oxidizing reaction and applies mechanically.Acetic acid reclaims and terminates, and under nitrogen protection, respectively with the clean tap water washing of 200Kg, 100Kg and 50Kg, stratification after stirring 30min, obtains aqueous phase I407.3Kg and oil phase I149.6Kg.Get oil phase and do GC and HPLC detection, GC result is, detects aldehydic acid compare 40.2:1 to methoxy toluene 54.3072%, aubepine 15.3044%, p-methoxybenzyl alcohol 0.4785% and acetic acid fennel ester 28.1905%, HPLC.
Under nitrogen protection, add in still kettle by the oil phase I149.6Kg of washing gained, add anhydrous sodium carbonate 5Kg, underpressure distillation obtains organic phase II138.5Kg.Heating up in a steamer the end adds 100Kg water, is neutralized to pH=2-3 with 72% sulfuric acid, filters, obtains anisic acid 5.2Kg.
Organic phase II138.5Kg rectifying under still temperature 109-125 DEG C and 6-8mmHg pressure obtains methoxy toluene 63.2Kg, GC purity 99.72%, under still temperature 125-132 DEG C and 3-5mmHg pressure, rectifying obtains aubepine 19.8Kg, GC purity 99.53%, cassie ketone 48.2Kg is obtained, GC purity 99.92% with rectifying under still temperature 135-138 DEG C and 3-5mmHg pressure.
Proceed in still kettle by aqueous phase I407.3Kg, open and stir, normal pressure, is warming up to 100-121 DEG C, and recycle-water 349Kg is used for applying mechanically, and heats up in a steamer end catalyst I and applies mechanically for oxidizing reaction.
200Kg water and 60Kg sodium hydroxide are put in hydrolytic reaction pot, 65-75 DEG C is warmed up to after dissolving, cassie ketone 48.2Kg is dripped in 30min, drip off rear insulation 1.5-2h, after reaction terminates, stratification, obtains aqueous phase II270.5Kg and p-methoxybenzyl alcohol crude product 37.3Kg, GC purity 99.15%.Then under still temperature 129-137 DEG C and 3-5mmHg pressure, carry out rectifying, obtain finished product p-methoxybenzyl alcohol 35.2Kg, GC purity 99.73%.
embodiment 3
488.8Kg acetic acid (KF<1%), 23.4Kg cobaltous acetate, 14.3Kg chromium acetate and 122.2Kg are put in dry stainless steel oxidation still to methoxy toluene, after being warmed up to 105-115 DEG C, pass into oxygen, stop passing into oxygen after pressure (gauge pressure) is for insulation reaction 2.5h under 0.09MPa, sampling is GC and HPLC and is detected, GC result is, aldehydic acid is detected to methoxy toluene 41.1563%, aubepine 29.5622%, p-methoxybenzyl alcohol 2.2164% and acetic acid fennel ester 26.2614%, HPLC and compares 13.0:1.
Oxidizing reaction terminates, and reclaims acetic acid KF=3.43%, acetic acid content 90.1%, is directly used in down batch oxidizing reaction and applies mechanically.Acetic acid reclaims and terminates, and under nitrogen protection, respectively with the clean tap water washing of 200Kg, 100Kg and 50Kg, stratification after stirring 30min, obtains aqueous phase I399.3Kg and oil phase I154.8Kg.Get oil phase and do GC and HPLC detection, GC result is, detects aldehydic acid compare 12.9:1 to methoxy toluene 41.1236%, aubepine 29.6537%, p-methoxybenzyl alcohol 2.0289% and acetic acid fennel ester 26.4344%, HPLC.
Under nitrogen protection, add in still kettle by the oil phase I154.8Kg of washing gained, add anhydrous sodium carbonate 6.2Kg, underpressure distillation obtains organic phase II145.6Kg.Heating up in a steamer the end adds 100Kg water, is neutralized to pH=2-3 with 72% sulfuric acid, filters, obtains anisic acid 6.0Kg.
Organic phase II145.6Kg rectifying under still temperature 108-122 DEG C and 6-8mmHg pressure obtains methoxy toluene 53.6Kg, GC purity 99.81%, under still temperature 124-129 DEG C and 3-5mmHg pressure, rectifying obtains aubepine 38.8Kg, GC purity 99.26%, cassie ketone 44.9Kg is obtained, GC purity 99.91% with rectifying under still temperature 136-139 DEG C and 3-5mmHg pressure.
Proceed in still kettle by aqueous phase I399.3Kg, open and stir, normal pressure, is warming up to 100-121 DEG C, and recycle-water 341.5Kg is used for applying mechanically, and heats up in a steamer end catalyst I and applies mechanically for oxidizing reaction.
200Kg water and 60Kg sodium hydroxide are put in hydrolytic reaction pot, 65-75 DEG C is warmed up to after dissolving, cassie ketone 44.9Kg is dripped in 30min, drip off rear insulation 1.5-2h, after reaction terminates, stratification, obtains aqueous phase II268.9Kg and p-methoxybenzyl alcohol crude product 35.7Kg, GC purity 99.32%.Then under still temperature 132-138 DEG C and 3-5mmHg pressure, carry out rectifying, obtain finished product p-methoxybenzyl alcohol 32.7Kg, GC purity 99.90%.
embodiment 4
By 488.8Kg acetic acid (KF<1%), 23.3Kg cobaltous acetate, chromium acetate 14.3Kg cerous acetate 10.0Kg and 122.2Kg puts in dry stainless steel oxidation still to methoxy toluene, after being warmed up to 105-115 DEG C, pass into oxygen, stop after insulation reaction 1.5h passing into oxygen under pressure is normal pressure (namely gauge pressure is 0MPa), sampling is GC and HPLC and is detected, GC result is, to methoxy toluene 55.6059%, aubepine 12.0937%, p-methoxybenzyl alcohol 0.6513% and acetic acid fennel ester 30.395%, HPLC detects aldehydic acid and compares 50.4:1.
Oxidizing reaction terminates, and reclaims acetic acid KF=5.27%, acetic acid content 89.92%, is directly used in down batch oxidizing reaction and applies mechanically.Acetic acid reclaims and terminates, and under nitrogen protection, uses the clean tap water of 200Kg, 100Kg and 50Kg respectively, and stratification after stirring 30min, obtains aqueous phase I409.5Kg and oil phase I147.0Kg.Get oil phase and do GC and HPLC detection, GC result is, detects aldehydic acid compare 51.0:1 to methoxy toluene 55.6129%, aubepine 12.0737%, p-methoxybenzyl alcohol 0.5574% and acetic acid fennel ester 30.7071%, HPLC.
Under nitrogen protection, add in still kettle by the oil phase I147.0Kg of washing gained, add anhydrous sodium carbonate 5Kg, underpressure distillation obtains organic phase II140.0Kg.Heating up in a steamer the end adds 100Kg water, is neutralized to pH=2-3 with 72% sulfuric acid, filters, obtains anisic acid 4.3Kg.
Organic phase II140.0Kg rectifying under still temperature 108-126 DEG C and 6-8mmHg pressure obtains methoxy toluene 64.5Kg, GC purity 99.93%, under still temperature 123-128 DEG C and 3-5mmHg pressure, rectifying obtains aubepine 15.6Kg, GC purity 99.39%, cassie ketone 52.0Kg is obtained, GC purity 99.85% with rectifying under still temperature 137-142 DEG C and 3-5mmHg pressure.
Proceed in still kettle by aqueous phase I409.5Kg, open and stir, normal pressure, is warming up to 100-121 DEG C, and recycle-water 356.9Kg is used for applying mechanically, and heats up in a steamer end catalyst I and applies mechanically for oxidizing reaction.
200Kg water and 60Kg sodium hydroxide are put in hydrolytic reaction pot, 65-75 DEG C is warmed up to after dissolving, cassie ketone 52.0Kg is dripped in 30min, drip off rear insulation 1.5-2h, after reaction terminates, stratification, obtains aqueous phase II267.4Kg and p-methoxybenzyl alcohol crude product 42.6Kg, GC purity 99.12%.Then under still temperature 136-139 DEG C and 3-5mmHg pressure, carry out rectifying, obtain finished product p-methoxybenzyl alcohol 39.8Kg, GC purity 99.54%.
embodiment 5
By 488.8Kg acetic acid (KF<1%), 23.3Kg cobaltous acetate, chromium acetate 14.3Kg cerous acetate 10.0Kg and 122.2Kg puts in dry stainless steel high-pressure oxidizing kettle to methoxy toluene, after being warmed up to 105-115 DEG C, setting oxygen pressure is 0.14-0.18MPa, continue to pass into oxygen, stop passing into oxygen after pressure (gauge pressure) is for insulation reaction 1.5h under 0.3MPa, sampling is GC and HPLC and is detected, GC result is, to methoxy toluene 41.1018%, aubepine 45.3527%, p-methoxybenzyl alcohol 0.2268% and acetic acid fennel ester 13.1939%, HPLC detects aldehydic acid and compares 8.0:1.
Oxidizing reaction terminates, and reclaims acetic acid KF=6.31%, acetic acid content 88.48%, is directly used in down batch oxidizing reaction and applies mechanically.Acetic acid reclaims and terminates, and under nitrogen protection, uses the clean tap water of 200Kg, 100Kg and 50Kg respectively, and stratification after stirring 30min, obtains aqueous phase I413.5Kg and oil phase I142.7Kg.Get oil phase and do GC and HPLC detection, GC result is, detects aldehydic acid compare 9.9:1 to methoxy toluene 41.1029%, aubepine 45.1617%, p-methoxybenzyl alcohol 0.1684% and acetic acid fennel ester 13.2977%, HPLC.
Under nitrogen protection, add in still kettle by the oil phase I142.7Kg of washing gained, add anhydrous sodium carbonate 5Kg, underpressure distillation obtains organic phase II136.9Kg.Heating up in a steamer the end adds 100Kg water, is neutralized to pH=2-3 with 72% sulfuric acid, filters, obtains anisic acid 5.2Kg.
Organic phase II136.9Kg rectifying under still temperature 109-123 DEG C and 6-8mmHg pressure obtains methoxy toluene 47.7Kg, GC purity 99.57%, under still temperature 125-130 DEG C and 3-5mmHg pressure, rectifying obtains aubepine 58.6Kg, GC purity 99.82%, cassie ketone 22.6Kg is obtained, GC purity 99.95% with rectifying under still temperature 136-140 DEG C and 3-5mmHg pressure.
Proceed in still kettle by aqueous phase I413.5Kg, open and stir, normal pressure, is warming up to 100-121 DEG C, and recycle-water 353.6Kg is used for applying mechanically, and heats up in a steamer end catalyst I and applies mechanically for oxidizing reaction.
192Kg water and 48Kg sodium hydroxide are put in hydrolytic reaction pot, 65-75 DEG C is warmed up to after dissolving, cassie ketone 22.6Kg is dripped in 30min, drip off rear insulation 1.5-2h, after reaction terminates, stratification, obtains aqueous phase II240.2Kg and p-methoxybenzyl alcohol crude product 19.3Kg, GC purity 99.22%.Then under still temperature 130-135 DEG C and 3-5mmHg pressure, carry out rectifying, obtain finished product p-methoxybenzyl alcohol 17.3Kg, GC purity 99.76%.
embodiment 6
The various recovered material of embodiment 5 are applied mechanically.
Acetic acid 468.9Kg acetic acid (KF=6.31% will be reclaimed, acetic acid content 88.48%, to methoxy toluene 6.61%), new acetic acid 73.9Kg (KF<1%), reclaim catalyzer, fresh acetic acid cobalt 0.5Kg, fresh acetic acid chromium 0.3Kg and 97.8Kg puts in dry stainless steel high-pressure oxidizing kettle to methoxy toluene, after being warmed up to 105-115 DEG C, setting oxygen pressure is 0.14-0.18MPa, continue to pass into oxygen, stop passing into oxygen after pressure (gauge pressure) is for insulation reaction 1.5h under 0.25MPa, sampling is GC and HPLC and is detected, GC result is, to methoxy toluene 39.4319%, aubepine 43.1831%, p-methoxybenzyl alcohol 0.1000% and acetic acid fennel ester 15.7635%, HPLC detects aldehydic acid and compares 7.8:1.
Oxidizing reaction terminates, and reclaims acetic acid KF=9.49%, acetic acid content 84.28%, is directly used in down batch oxidizing reaction and applies mechanically.Acetic acid reclaims and terminates, and under nitrogen protection, uses the clean tap water of 200Kg, 100Kg and 50Kg respectively, and stratification after stirring 30min, obtains aqueous phase I410.5Kg and oil phase I149.0Kg.Get oil phase and do GC and HPLC detection, GC result is, detects aldehydic acid compare 8.4:1 to methoxy toluene 39.4233%, aubepine 43.1812%, p-methoxybenzyl alcohol 0.0591% and acetic acid fennel ester 15.8286%, HPLC.
Under nitrogen protection, add in still kettle by the oil phase I149.0Kg of washing gained, add anhydrous sodium carbonate 5Kg, underpressure distillation obtains organic phase II139.5Kg.Heating up in a steamer the end adds 100Kg water, is neutralized to pH=2-3 with 72% sulfuric acid, filters, obtains anisic acid 5.7Kg.
Organic phase II139.5Kg rectifying under still temperature 111-122 DEG C and 6-8mmHg pressure obtains methoxy toluene 45.8Kg, GC purity 99.87%, under still temperature 124-128 DEG C and 3-5mmHg pressure, rectifying obtains aubepine 55.8Kg, GC purity 99.37%, cassie ketone 27.0Kg is obtained, GC purity 99.59% with rectifying under still temperature 135-139 DEG C and 3-5mmHg pressure.
Proceed in still kettle by aqueous phase I410.5Kg, open and stir, normal pressure, is warming up to 100-121 DEG C, and recycle-water 352.1Kg is used for applying mechanically, and heats up in a steamer end catalyst I and applies mechanically for oxidizing reaction.
192Kg water and 48Kg sodium hydroxide are put in hydrolytic reaction pot, 65-75 DEG C is warmed up to after dissolving, cassie ketone 27.0Kg is dripped in 30min, drip off rear insulation 1.5-2h, after reaction terminates, stratification, obtains aqueous phase II241.4Kg and p-methoxybenzyl alcohol crude product 22.8Kg, GC purity 99.36%.Then under still temperature 130-137 DEG C and 3-5mmHg pressure, carry out rectifying, obtain finished product p-methoxybenzyl alcohol 20.7Kg, GC purity 99.65%.
Should be appreciated that, although the present invention has been described in detail in conjunction with example, above-mentioned explanation has been intended to illustrate, and limits its summary of the invention never in any form.Concerning art technology people, farthest can utilize the present invention based on explanation herein, and multiple amendment or modification can be carried out not departing from right of the present invention or spirit.Each reference that the application quotes, which is hereby incorporated by reference.
Claims (9)
1. dioxygen oxidation prepares a co-production for correspondent alcohol, ester, aldehyde and acid to methoxy toluene, it is characterized in that, comprises the following steps:
Step 1), add in oxidizing reactor methoxy toluene, catalyst I and solvent, pass into oxygen at a certain temperature, stopped reaction after reaction certain hour,
Described solvent is acetic acid, acetic acid be 1 ~ 50:1 to the mole dosage ratio of methoxy toluene,
Catalyst I is one of cobaltous acetate, manganous acetate, chromium acetate, cerous acetate, acid chloride, ironic acetate, venus crystals, or the composite catalyst of their compositions; Used catalyst I be 0.1 ~ 2.0:1 to the mole dosage ratio of methoxy toluene;
Step 2), oxidizing reaction terminates, recycling design acetic acid, controls its moisture 0 ~ 50%, for applying mechanically, then adding washing and going catalyst I, obtain organic phase I and aqueous phase I;
Step 3), alkali is added in organic phase I, alkali used is basic metal inorganic acid salt or oxyhydroxide, alkali adds in solid form, alkali be 0.01 ~ 1:1 to the mole dosage ratio of methoxy toluene, decompression steams organic phase II, heats up in a steamer the end to add with sour adjust pH=1-5 after water, filters and obtains anisic acid;
Step 4), aqueous phase I Distillation recovery water, without the need to any process, to be directly used in step 2 washing and to apply mechanically, and heats up in a steamer after the end adds catalyst I and solvent, is directly used in oxidizing reaction and applies mechanically, the amount adding catalyzer be catalyzer first charging capacity 1 ~ 30%;
Step 5), organic phase II rectifying obtains finished product aubepine and cassie ketone;
Step 6), cassie ketone alkaline hydrolysis, alkaline hydrolysis alkali used is the aqueous solution of an alkali metal salt or oxyhydroxide, obtains anisy alcohol crude product, obtains anisy alcohol sterling through rectifying.
2. preparation method according to claim 1, is characterized in that,
In step 1, acetic acid used be 5 ~ 15:1 to the mole dosage ratio of methoxy toluene; Used catalyst I be 0.2 ~ 1.0 to the mole dosage ratio of methoxy toluene.
3. preparation method according to claim 1, is characterized in that,
In step 1, the temperature of oxidizing reaction is 80 ~ 120 DEG C; Oxidizing reaction gauge pressure is 0 ~ 1.2MPa.
4. preparation method according to claim 3, is characterized in that,
In step 1, the temperature of oxidizing reaction is 100 ~ 115 DEG C; Oxidizing reaction gauge pressure is 0 ~ 0.5MPa.
5., according to the preparation method one of Claims 1-4 Suo Shu, it is characterized in that,
In step 2, recycling design acetic acid, controls its moisture 0 ~ 30%.
6., according to the preparation method one of Claims 1-4 Suo Shu, it is characterized in that,
In step 2, after solvent recuperation terminates, add water and catalyst I washing be separated, washing times is 1 ~ 10 time.
7., according to the preparation method one of Claims 1-4 Suo Shu, it is characterized in that,
In step 3, alkali used is sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide; Alkali adds in solid form, alkali with to the mole dosage of methoxy toluene than 0.05 ~ 0.5:1;
Decompression steams organic phase II, heats up in a steamer the end to add after water with acid for adjusting pH value=2-3.
8., according to the preparation method one of Claims 1-4 Suo Shu, it is characterized in that,
In step 6, alkaline hydrolysis alkali used is the aqueous solution of sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide; Temperature of reaction is 60 ~ 120 DEG C.
9. preparation method according to claim 8, is characterized in that,
In step 6, alkaline hydrolysis alkali used is the aqueous solution of sodium hydroxide, potassium hydroxide; Temperature of reaction is 80 ~ 110 DEG C.
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