CN115304461A - Novel condensation reaction method of dibenzoyl methane - Google Patents
Novel condensation reaction method of dibenzoyl methane Download PDFInfo
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- CN115304461A CN115304461A CN202210878727.4A CN202210878727A CN115304461A CN 115304461 A CN115304461 A CN 115304461A CN 202210878727 A CN202210878727 A CN 202210878727A CN 115304461 A CN115304461 A CN 115304461A
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- Prior art keywords
- methanol
- reaction
- condensation
- heat preservation
- dibenzoylmethane
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- NZZIMKJIVMHWJC-UHFFFAOYSA-N dibenzoylmethane Chemical compound C=1C=CC=CC=1C(=O)CC(=O)C1=CC=CC=C1 NZZIMKJIVMHWJC-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000006482 condensation reaction Methods 0.000 title claims abstract description 14
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 114
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 42
- 238000006243 chemical reaction Methods 0.000 claims abstract description 27
- KWOLFJPFCHCOCG-UHFFFAOYSA-N Acetophenone Chemical compound CC(=O)C1=CC=CC=C1 KWOLFJPFCHCOCG-UHFFFAOYSA-N 0.000 claims abstract description 22
- QPJVMBTYPHYUOC-UHFFFAOYSA-N methyl benzoate Chemical compound COC(=O)C1=CC=CC=C1 QPJVMBTYPHYUOC-UHFFFAOYSA-N 0.000 claims abstract description 22
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims abstract description 21
- 238000004321 preservation Methods 0.000 claims abstract description 14
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 11
- 229940095102 methyl benzoate Drugs 0.000 claims abstract description 11
- 230000020477 pH reduction Effects 0.000 claims abstract description 7
- 239000003513 alkali Substances 0.000 claims abstract description 6
- 238000004821 distillation Methods 0.000 claims abstract description 6
- 238000010992 reflux Methods 0.000 claims abstract description 6
- 238000005406 washing Methods 0.000 claims abstract description 6
- 238000001816 cooling Methods 0.000 claims abstract description 4
- 239000002994 raw material Substances 0.000 claims abstract description 3
- 239000008096 xylene Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 238000009833 condensation Methods 0.000 claims 6
- 230000005494 condensation Effects 0.000 claims 6
- WQDUMFSSJAZKTM-UHFFFAOYSA-N Sodium methoxide Chemical compound [Na+].[O-]C WQDUMFSSJAZKTM-UHFFFAOYSA-N 0.000 abstract description 20
- 238000003786 synthesis reaction Methods 0.000 abstract description 7
- 230000015572 biosynthetic process Effects 0.000 description 5
- 239000003054 catalyst Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 3
- QDRKDTQENPPHOJ-UHFFFAOYSA-N sodium ethoxide Chemical compound [Na+].CC[O-] QDRKDTQENPPHOJ-UHFFFAOYSA-N 0.000 description 3
- 239000002585 base Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 231100000252 nontoxic Toxicity 0.000 description 2
- 230000003000 nontoxic effect Effects 0.000 description 2
- KRIOVPPHQSLHCZ-UHFFFAOYSA-N phenyl propionaldehyde Natural products CCC(=O)C1=CC=CC=C1 KRIOVPPHQSLHCZ-UHFFFAOYSA-N 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000003512 Claisen condensation reaction Methods 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 229920000122 acrylonitrile butadiene styrene Polymers 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- RWCCWEUUXYIKHB-UHFFFAOYSA-N benzophenone Chemical compound C=1C=CC=CC=1C(=O)C1=CC=CC=C1 RWCCWEUUXYIKHB-UHFFFAOYSA-N 0.000 description 1
- 239000012965 benzophenone Substances 0.000 description 1
- QRUDEWIWKLJBPS-UHFFFAOYSA-N benzotriazole Chemical compound C1=CC=C2N[N][N]C2=C1 QRUDEWIWKLJBPS-UHFFFAOYSA-N 0.000 description 1
- 239000012964 benzotriazole Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- -1 calcium-zinc hydroxy acid salt Chemical class 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000001944 continuous distillation Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 235000013350 formula milk Nutrition 0.000 description 1
- 239000012760 heat stabilizer Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000004611 light stabiliser Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004597 plastic additive Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000010025 steaming Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000009967 tasteless effect Effects 0.000 description 1
- 229920001169 thermoplastic Polymers 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/45—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by condensation
- C07C45/455—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by condensation with carboxylic acids or their derivatives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/68—Preparation of metal alcoholates
- C07C29/70—Preparation of metal alcoholates by converting hydroxy groups to O-metal groups
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a novel condensation reaction method of dibenzoyl methane, relates to the technical field of chemical synthesis, solves the problem of safety risk caused by using sodium methoxide in the conventional condensation reaction process of dibenzoyl methane, and comprises the following steps: s1, adding 2000-4000L of dimethylbenzene into a reaction kettle by taking dimethylbenzene and methanol as raw materials; 120-150 Kg of methanol, then adding sodium hydroxide again under the steam temperature rise reflux of 70-80 ℃, carrying out heat preservation reaction for 1 hour, after the heat preservation reaction is finished, raising the temperature to 130 ℃, dropwise adding industrial methanol with different contents from a high-level metering tank, and carrying out distillation treatment in the dropwise adding process; s2, after the distillation treatment is finished, cooling to 30-80 ℃, adding methyl benzoate, heating to 130-140 ℃, continuing to dropwise add acetophenone from the high-level metering tank for heat preservation reaction for 2-3 hours, and obtaining dibenzoyl methane through sulfuric acid acidification, alkali washing and concentration.
Description
Technical Field
The invention belongs to the technical field of chemical synthesis, and particularly relates to a novel condensation reaction method of dibenzoyl methane.
Background
Dibenzoyl methane (DBM) is an important light and heat stabilizer for thermoplastic plastics with a beta-diketone structure, and the product is nontoxic and odorless and is widely applied to PVC plastics and ABS resin. Compared with other common plastic additives, the dibenzoyl methane has the advantages of wider absorptivity and lower transmissivity to outdoor ultraviolet rays, has better ultraviolet absorption performance than common benzophenone and benzotriazole ultraviolet absorbers, has good thermal stability, chemical stability and light stability, is nontoxic, tasteless and does not pollute products, can be used as a co-stabilizer of a calcium-zinc hydroxy acid salt stabilizing system and is commonly used for manufacturing PVC mineral water bottles and baby milk products, is synthesized by adding methyl benzoate, acetophenone and strong base into a xylene solvent for condensation reaction, and the strong base can be selected from sodium hydroxide, sodium methoxide, sodium ethoxide and the like. The sodium methoxide as a catalyst has high synthesis yield (the synthesis yield is 85-90 percent in literature reports), but the sodium methoxide is extremely easy to absorb moisture and belongs to spontaneous combustion articles, once the sodium methoxide is poorly managed, and equipment facilities have defects or illegal operations can cause fire explosion in the processes of transportation, storage and use, and once accidents occur, personal casualties and huge economic losses are caused, so that extremely bad influence is caused on the whole society; the synthesis yield of sodium ethoxide as a catalyst is not much different from that of sodium methoxide (the synthesis yield is 85-90 percent reported in documents), the same safety risk as that of sodium methoxide also exists, and the price of sodium ethoxide is more expensive; sodium hydroxide as a catalyst is safe but has low synthesis yield (the reaction yield is about 60% when sodium hydroxide as a catalyst is reported in the literature). At present, the main equation for the industrial production of Dibenzoylmethane (DBM) is as follows:
(1) Esterification reaction
(2) Condensation reaction
Carrying out a third acidification reaction
Based on the above, the present inventors found that the following problems exist: the problem of safety risk and the like caused by sodium methoxide in the existing condensation reaction process of dibenzoyl methane.
Therefore, in view of the above, research and improvement are made for the existing structure and deficiency, and a new method for condensation reaction of dibenzoylmethane is provided, so as to achieve the purpose of more practical value.
Disclosure of Invention
In order to solve the technical problems, the invention provides a novel condensation reaction method of dibenzoylmethane, which aims to solve the problem of safety risk caused by using sodium methoxide in the conventional condensation reaction process of dibenzoylmethane.
The purpose and the effect of the novel condensation reaction method of dibenzoyl methane are achieved by the following specific technical means:
a novel condensation reaction method of dibenzoyl methane comprises the following steps:
s1, adding 2000-4000L of dimethylbenzene into a reaction kettle by taking dimethylbenzene and methanol as raw materials; 120-150 Kg of methanol, then adding sodium hydroxide again under the steam temperature rise reflux of 70-80 ℃, carrying out heat preservation reaction for 1 hour, after the heat preservation reaction is finished, raising the temperature to 130 ℃, dropwise adding industrial methanol with different contents from a high-level metering tank, and carrying out distillation treatment in the dropwise adding process;
s2, after the distillation treatment is finished, cooling to 30-80 ℃, adding methyl benzoate, heating to 130-140 ℃, continuing to dropwise add acetophenone from the high-level metering tank for heat preservation reaction for 2-3 hours, and obtaining the dibenzoyl methane through sulfuric acid acidification, alkali washing and concentration.
Further, the molar ratio of the amount of the methyl benzoate to the acetophenone is 1-3:1.
Furthermore, the molar ratio of the industrial methanol to the sodium hydroxide is 2-5:1.
Further, the molar ratio of the amount of the acetophenone to the sodium hydroxide is 1:1 to 2.
Further, the industrial methanol can be a mixture of fresh industrial methanol, methanol and xylene in any one or more proportions, and the moisture content of the industrial methanol is less than 0.5%.
Further, the water content of the methanol is less than 0.5%.
Further, methanol in the high-level dropwise adding tank is fed from the bottom of the reaction kettle, and the position difference between the bottom of the high-level tank and the top of the reaction kettle is more than 1500 mm.
Compared with the prior art, the invention has the following beneficial effects:
the invention adopts the method of continuous distillation and dehydration to prepare sodium methoxide in a xylene solvent by using sodium hydroxide and methanol, and then adds methyl benzoate and acetophenone to carry out claisen condensation reaction, thereby ensuring the production safety and the product yield, and simultaneously preparing the methyl benzoate from the byproduct methanol, thereby realizing the recycling.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Example 1:
3000L of xylene is added into a dry 6300L reaction kettle; stirring 120Kg of methanol, adding 150Kg of crushed sodium hydroxide, starting steam, heating to 70-80 ℃ for reflux, and reacting for 1 hour under heat preservation; then heating to 130 ℃, beginning to dropwise add fresh industrial methanol from a high-level metering tank, wherein the flow rate is about 120Kg/h, altogether 480Kg of fresh industrial methanol is dropwise added, after dropwise addition, methanol and water are evaporated while dropwise adding, after dropwise addition, cooling water is started to cool to 50 ℃, methyl benzoate is added to 700Kg, then heating to 130 ℃, beginning to dropwise add acetophenone 450Kg for reaction, after dropwise addition for 2 hours, after dropwise addition, carrying out heat preservation reaction for 2 hours, and then carrying out processes of sulfuric acid acidification, alkali washing, concentration and the like to obtain dibenzoylmethane 751Kg, the purity is 99.01%, and the yield is 88.62%.
Example 2:
3000L of xylene is added into a dry 6300L reaction kettle; stirring 150Kg of methanol, adding 187.5Kg of crushed sodium hydroxide, starting steam, heating to 70-80 ℃ for reflux, and reacting for 1 hour under heat preservation; then heating to 130 ℃, beginning to drop fresh methanol from a high-level metering tank with the flow rate of about 150Kg/h, dropping 750Kg of fresh methanol, after 5h, steaming methanol and water while dropping, starting cooling water after dropping, cooling to 55 ℃, adding 1200Kg of methyl benzoate, then heating to 130 ℃, beginning to drop 563Kg of acetophenone for reaction, after 2.5 h, dropping for 3 h, and then carrying out sulfuric acid acidification, alkali washing, concentration and other processes to obtain 953Kg of dibenzoyl methane with the purity of 99.23% and the yield of 90.06%.
Example 3:
adding 2500L of dimethylbenzene into a dry 6300L reaction kettle; 150Kg of methanol is stirred, 187.5Kg of crushed sodium hydroxide is added, steam is started to heat up to 70-80 ℃ for reflux, and the reaction is carried out for 1 hour under the condition of heat preservation; then heating to 130 ℃, beginning to dropwise add and recover methanol (the methanol content is 71.4 percent, the xylene content is 28.6 percent) from a high-level metering tank, the flow rate is about 210Kg/h, 1050Kg of methanol is dropwise recovered, after dropwise adding is finished, methanol and water are evaporated while dropwise adding is carried out, after dropwise adding is finished, cooling water is started to be cooled to 55 ℃, methyl benzoate 1200Kg is added, then heating to 130 ℃, beginning to dropwise add acetophenone 563Kg for reaction, after 2.5 hours of dropwise adding is finished, after dropwise adding is finished, the heat preservation reaction is carried out for 3 hours, and then processes such as sulfuric acid acidification, alkali washing, concentration and the like are carried out to obtain 940Kg of dibenzoyl methane, the purity is 99.05 percent, and the yield is 88.67 percent.
The embodiments of the present invention have been presented for purposes of illustration and description, and are not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.
Claims (7)
1. A novel condensation reaction method of dibenzoyl methane is characterized by comprising the following steps:
s1, adding 2000-4000L of dimethylbenzene into a reaction kettle by taking dimethylbenzene and methanol as raw materials; 120-150 Kg of methanol, then adding sodium hydroxide again under the steam temperature rise reflux of 70-80 ℃, carrying out heat preservation reaction for 1 hour, after the heat preservation reaction is finished, raising the temperature to 130 ℃, dropwise adding industrial methanol with different contents from a high-level metering tank, and carrying out distillation treatment in the dropwise adding process;
s2, after the distillation treatment is finished, cooling to 30-80 ℃, adding methyl benzoate, heating to 130-140 ℃, continuing to dropwise add acetophenone from the high-level metering tank for heat preservation reaction for 2-3 hours, and obtaining the dibenzoyl methane through sulfuric acid acidification, alkali washing and concentration.
2. The novel process for the condensation of dibenzoylmethane as claimed in claim 1, wherein: the molar ratio of the amount of the methyl benzoate to the acetophenone is 1-3:1.
3. The novel process for the condensation of dibenzoylmethane as claimed in claim 1, wherein: the molar ratio of the amount of the industrial methanol to the amount of the sodium hydroxide is 2-5:1.
4. The novel process for the condensation of dibenzoylmethane as claimed in claim 1, wherein: the molar ratio of the amount of the acetophenone to the amount of the sodium hydroxide is 1:1 to 2.
5. The novel process for the condensation of dibenzoylmethane as claimed in claim 1, wherein: the industrial methanol can be fresh industrial methanol, methanol and xylene, and the moisture of the industrial methanol is less than 0.5%.
6. The novel process for the condensation of dibenzoylmethane as claimed in claim 1, wherein: the water content of the methanol is less than 0.5%.
7. The novel process for the condensation of dibenzoylmethane as claimed in claim 1, wherein: methanol in the high-level dropwise adding tank is fed from the bottom of the reaction kettle, and the position difference between the bottom of the high-level tank and the top of the reaction kettle is more than 1500 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210878727.4A CN115304461A (en) | 2022-07-25 | 2022-07-25 | Novel condensation reaction method of dibenzoyl methane |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210878727.4A CN115304461A (en) | 2022-07-25 | 2022-07-25 | Novel condensation reaction method of dibenzoyl methane |
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| CN115304461A true CN115304461A (en) | 2022-11-08 |
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| CN202210878727.4A Pending CN115304461A (en) | 2022-07-25 | 2022-07-25 | Novel condensation reaction method of dibenzoyl methane |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102285874A (en) * | 2011-09-08 | 2011-12-21 | 安徽佳先功能助剂股份有限公司 | Method for crystallizing dibenzoyl methane |
| WO2012084770A1 (en) * | 2010-12-20 | 2012-06-28 | Dsm Ip Assets B.V. | Process for the manufacture of dibenzoylmethane derivatives |
| CN103058845A (en) * | 2013-01-08 | 2013-04-24 | 河南师范大学 | Dibenzoylmethane preparation method |
| CN103483172A (en) * | 2013-09-02 | 2014-01-01 | 河南师范大学 | Preparation for dibenzoyl methane |
| CN110818543A (en) * | 2018-08-09 | 2020-02-21 | 山东瑞丰高分子材料股份有限公司燕崖分公司 | Novel method for efficiently synthesizing dibenzoyl methane |
| CN112299978A (en) * | 2020-11-12 | 2021-02-02 | 董启林 | Synthesis process of dibenzoyl methane |
-
2022
- 2022-07-25 CN CN202210878727.4A patent/CN115304461A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012084770A1 (en) * | 2010-12-20 | 2012-06-28 | Dsm Ip Assets B.V. | Process for the manufacture of dibenzoylmethane derivatives |
| CN102285874A (en) * | 2011-09-08 | 2011-12-21 | 安徽佳先功能助剂股份有限公司 | Method for crystallizing dibenzoyl methane |
| CN103058845A (en) * | 2013-01-08 | 2013-04-24 | 河南师范大学 | Dibenzoylmethane preparation method |
| CN103483172A (en) * | 2013-09-02 | 2014-01-01 | 河南师范大学 | Preparation for dibenzoyl methane |
| CN110818543A (en) * | 2018-08-09 | 2020-02-21 | 山东瑞丰高分子材料股份有限公司燕崖分公司 | Novel method for efficiently synthesizing dibenzoyl methane |
| CN112299978A (en) * | 2020-11-12 | 2021-02-02 | 董启林 | Synthesis process of dibenzoyl methane |
Non-Patent Citations (1)
| Title |
|---|
| 上海信诚化工厂技术股: "用氢氧化钠制取甲醇钠", 化学世界, no. 4, 31 December 1965 (1965-12-31), pages 155 - 157 * |
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