CN100366607C - Process for preparing polyisocyanate by solid phosgene - Google Patents
Process for preparing polyisocyanate by solid phosgene Download PDFInfo
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- CN100366607C CN100366607C CNB200510008982XA CN200510008982A CN100366607C CN 100366607 C CN100366607 C CN 100366607C CN B200510008982X A CNB200510008982X A CN B200510008982XA CN 200510008982 A CN200510008982 A CN 200510008982A CN 100366607 C CN100366607 C CN 100366607C
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- solid phosgene
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Abstract
The present invention relates to a method for preparing 1, 2-dialkoxy-3-fluorobenzene from an intermediate product (2-fluoro-6-halogenated phenol). In the method, 2-fluorophenol is used as a raw material; after sulfonation, halogenation and de-protection, an intermediate product (2-fluoro-6-halogenated phenol) is obtained; then the intermediate product (2-fluoro-6-halogenated phenol) is treated with multi-step reaction, such as etherification reaction, hydroxy introduction reaction, secondary etherification reaction, etc., to obtain 1, 2-dialkoxy-3-fluorobenzene; or the intermediate product (2-fluoro-6-halogenated phenol) is treated with hydroxylation and etherification to obtain 1, 2-dialkoxy-3-fluorobenzene. The method of the present invention has the advantages of low cost and high yield, and is suitable for industrialized production.
Description
Technical field
The present invention relates to a kind of method of utilizing solid phosgene and polyamines or its salt to prepare polyisocyanates.
Background technology
Isocyanic ester is generally used for preparing urethane resin, coating and tackiness agent.As everyone knows, urethane has been widely used at aspects such as optical material, automobile and structure material, sealing material, daily necessities owing to have the favorable mechanical performance.In addition, with amino acid, for example Methionin is the polyisocyanates and the urethane resin of feedstock production, owing to have excellent biological compatibility, can be used as biomedical uses.
The method for preparing at present isocyanic ester is normally utilized the reaction of phosgene and amine.At patent US5,136,086, US4,419,295, among JP2002-003462, JP06-234722, CN1125718A, CN1197793A, CN1516688A and the EP424836, all be to utilize phosgene that amine is carried out phosgenation reaction to prepare isocyanic ester.But have a lot of problems because having used phosgene in this method, for example phosgene severe toxicity, explosive belongs to the high-risk material, uses to be subjected to a lot of restrictions; And be difficult to transportation, preserve complicated operating process.In addition, because phosgene is gas at normal temperatures and pressures, solubleness in solvent is limited, therefore for fully carrying out of guaranteeing to react, reaction times needs very long, so just increase the consumption of phosgene in the reaction greatly, increased difficulty and environmental protection pressure that tail gas absorbs, made production cost improve and production security decline simultaneously.Therefore this method is unsuitable for the scale operation isocyanic ester.
In patent CN1436772A, utilize trichloromethylchloroformate (superpalite) and Armeen, primary aromatic amine and aromatic diamine to prepare polyisocyanates, productive rate reaches 80-96%.Though it is the toxicity of trichloromethylchloroformate is lower than phosgene,, therefore also not obvious to the improvement effect of phosgenation reaction because the preparation process of trichloromethylchloroformate is used phosgene.And, in storage and use, also there are some obstacles because trichloromethylchloroformate is a liquid.
Substitute brilliant because these shortcomings and restriction that phosgene and trichloromethylchloroformate exist in application, solid phosgene (triphosgene, two-(trichloromethyl) carbonic ether) become ideal.It is similar with trichloromethylchloroformate to phosgene that solid phosgene prepares the reaction principle of isocyanic ester, all is to slough HCl with the amine condensation earlier, sloughs HCl then under heating condition again, obtains isocyanic ester.But solid phosgene is safe in utilization, easy to operate, has very big advantage aspect industrial applications.
Abundant national expenditures solid phosgene of Deng Yong and clock and β-phenylethylamine reaction obtains β-styroyl isocyanic ester, in the reaction phenylethylamine drips of solution is added in the ice bath refrigerative solid phosgene solution, then in reflux temperature reaction (West China pharmaceutical journal, 2000,15 (4), 289).Human solid phosgene and gamma-amino propyl-siloxane prepared in reaction γ-isocyanic ester propyl-siloxanes such as Bai Zhengwu, the drips of solution with solid phosgene in the reaction be added to-amine aqueous solution of 5-0 ℃ in, subsequently in 50 ℃ of reactions (chemistry and biotechnology, 2004 (2), 16).Utilize solid phosgene to 1 among the patent CN1394851, the 5-diaminonaphthalene carries out phosgenation, with 1, and reaction at high temperature again after 5-diaminonaphthalene solution joins in the solid phosgene at low temperatures.This several method all be by reinforced at low temperatures with the process of control amine with the condensation reaction of solid phosgene, and then heating carries out elimination reaction, needs cool off earlier reheat during reaction, process is more loaded down with trivial details.And phosgenation reaction carries out under pressurized conditions in patent CN1394851, and to having relatively high expectations of conversion unit, the HCl that forms in the reaction can not discharge simultaneously, makes that HCl content increases in the finished product.In addition, 1, the speed that 5-diaminonaphthalene solution joins in the solid phosgene solution is very fast, may cause local superheating, makes side reaction increase, and might form a large amount of tarring products.The increase of by product quantity in the finished product makes that the aftertreatment purification process of reaction is more complicated, greatly reduces the purity of product.These isocyanic ester that all can cause obtaining can not satisfy service requirements at aspects such as color and luster, mechanical propertys when preparation urethane.
More than several methods of utilizing solid phosgene to prepare isocyanic ester all only limit to primary amine and diamines, the phosgenation reaction of the salt that forms for the polyamines more than the triamine and amine and acid is not all discussed.Because the phosgenation reaction of the above polyamines of triamine is more difficult, reaction needs higher temperature usually, and in the longer reaction times, the by product kind that may form in the reaction is more, and therefore condition and the control in the reaction process for reaction requires higher.In addition, can dissociate out in the phosgenation reaction process for the acid molecule in the amine salt, contain the formation that a large amount of acid can suppress isocyanic ester in the reaction system, so the phosgenation reaction of amine salt is also comparatively difficult, is preferably in and constantly discharges the acid that forms in the reaction process.The present invention is primarily aimed at these problems and has invented a kind of polyamines and its salt phosgenation reaction of being applicable to and prepare the method for isocyanic ester.
The present invention is when utilizing solid phosgene and polyamines prepared in reaction isocyanic ester, by in reactor, dripping the method for polyamines and its salts solution and solid phosgene solution, each process that adds a small amount of reactant with the control reaction, reach the purpose that reduces by product, and avoid the formation of tarring product as far as possible.Just at high temperature carry out, and remain synthesis under normal pressure when the phosgenation reaction among the present invention is initial, do not have particular requirement for equipment like this, and help the effusion of HCl.Method of the present invention more is applicable to the suitability for industrialized production polyisocyanates, and the tarring product that forms in the reaction process is less, and HCl content is low in the product, and the polyisocyanates product that obtains can be used to prepare the polyurethane material that color, purity etc. is had relatively high expectations.
Summary of the invention
The present invention substitutes phosgene with solid phosgene, prepares polyisocyanates with polyamines or its reactant salt.Described polyamines contains two or more amino, and described polyamines can be fat polyamine by described polyamines, and aliphatic chain can be straight or branched, quadrol, 1 for example, 6-hexanediamine, 1,4-butanediamine, 1,4-pentamethylene diamine, 1,2,6-hexanediamine, 1,3,6-heptamethylene diamine etc.; Also can be for not being with or having substituent cyclic aliphatic polyamines or an aralkyl polyamines, for example 1,4-diamino-cyclohexane, 1,3-diamino-cyclohexane, adjacent dibenzylamine, a dibenzylamine, to dibenzylamine, 2-(beta-aminoethyl) benzylamine etc.; Also can be for containing the aromatic multi-amine of two or more amino, for example 2,4-tolylene diamine, 2,5-tolylene diamine, 1,2,4-benzene triamine etc.; Can also be the polyamines for preparing by the amino acid esterification, for example the diamines or the triamine that obtain of amino acid such as Methionin, glycine, L-glutamic acid, tryptophane, Gelucystine and thanomin reaction.Described salt can preferably use hydrochloride for hydrochloride, vitriol, nitrate or the phosphoric acid salt etc. of above various amine.Can use single amine or its salt in the reaction, also can use mixed amine or/and its salt.
The mol ratio of amine and solid phosgene is 1 among the present invention: 1-1: 20, preferred 1: 2-1: 5.
Solvent with solid phosgene reaction among the present invention is to phosgenation reaction inert solvent, and arene for example is as benzene,toluene,xylene etc.; Or the halogenated aryl hydrocarbon class, as chlorobenzene, orthodichlorobenzene etc.; Or the benzene nitrile, as cyanobenzene; Or aliphatics and aromatic ester class, pentyl acetate for example, ethyl benzoate etc.The preferred orthodichlorobenzene of solvent.Solvent load is 1-10 a times of reaction raw materials gross weight.Solvent is used further to this reaction after recyclable after the reaction.
When reaction is reinforced among the present invention, amine and solid phosgene are dissolved in respectively in the solvent, are added drop-wise in the reactor.Control the condensation reaction of amine and solid phosgene by the mode that only adds a small amount of reaction raw materials at every turn.
The drips of solution of polyamines and solid phosgene is added to when in the reactor condensation reaction taking place among the present invention, and HCl is sloughed in the intermediate product heating, obtains polyisocyanates.Two-step reaction carries out simultaneously, and temperature is at 100-200 ℃, and preferred 140-150 ℃, reaction times 5-15 hour, preferred 8-10 hour.
After the polyamines of predetermined amount and solid phosgene solution splashed into reactor and uniform mixing fully among the present invention, at 100-200 ℃, preferred 140-150 ℃ was continued slaking 1-5 hour, preferred 2-3 hour down.
Can reach more than 85% through productive rate behind the vacuum fractionation, the content of NCO can reach more than 95% of theoretical value in the product.
Following examples describe the present invention in detail, but the present invention is not limited thereto.
Embodiment 1:
Lysine triisocyanate (LTI):
Add 449.6g (4.31mol) 35%HCl solution in the 1L four-hole boiling flask and in 30 minutes, drip 167.2g (2.74mol) thanomin, dropwise the back and add 250.0g (1.37mol) lysine hydrochloride, and 45 ℃ of following stirring reactions 10 minutes.Temperature is risen to 110 ℃, be decompressed to 4KPa, boil off the moisture content in the reaction system.Recover to feed HCl gas reaction 3 hours behind the normal pressure, again pressure reducing and steaming moisture content wherein.This process repeats for several times, and lysine hydrochloride runs out of the back stopped reaction, adds orthodichlorobenzene (ODCB) and methanol crystallization, and crystal obtains Methionin amino ethyl ester tri hydrochloride (LAET) for several times with the ODCB washing.
The 2500ml reactor is joined mechanical stirring and two cover droppers.In reactor, add 100ml orthodichlorobenzene (ODCB); respectively 298.5 (1mol) Methionin amino ethyl ester tri hydrochloride (LAET) is dissolved in 500ml ODCB; 594g (2mol) is two-and (trichloromethyl) carbonic ether (solid phosgene) is dissolved among the 1000ml ODCB, under nitrogen protection these two kinds of solution joined in the Dropping feeder.Temperature of reaction kettle remains on 145 ℃, drips the ODCB solution of LAET and solid phosgene in 10 hours.Dropwise the back and be incubated 2 hours under this temperature, the mixing solutions that obtains adds gac and stirs decolouring, suction filtration after the cooling.Filtrate decompression boils off rectifying behind the solvent, collects the cut of 80-85 ℃/60mmHg.Product by analysis, LTI content 91.5% (HPLC), NCO content 46.23wt% (theoretical value 47.2wt%), HCl content 0.2wt%, ODCB content 0.08wt%.
Embodiment 2:
Lysine triisocyanate (LTI):
Except that two-(trichloromethyl) carbonic ether changes into the 445.5g (1.5mol), other reaction conditionss obtain LTI content 68.6% (HPLC) in the product, NCO content 40.3wt% (theoretical value 47.2wt%) with embodiment 1, HCl content 0.70wt%, ODCB content 0.81wt%.
Embodiment 3:
Lysine triisocyanate (LTI):
Except that two-(trichloromethyl) carbonic ether changes into the 891g (3mol), other reaction conditionss obtain LTI content 86.3% (HPLC) in the product, NCO content 43.6wt% (theoretical value 47.2wt%) with embodiment 1, HCl content 0.35wt%, ODCB content 0.31wt%.
Embodiment 4:
Hexamethylene diisocyanate:
116g (1mol) 1, the 300ml toluene solution of 6-hexanediamine, 386g (1.3mol) be two-and the 600ml toluene solution of (trichloromethyl) carbonic ether is added drop-wise in the 100ml toluene by the method among the embodiment 1, add insulation 2 hours under uniform temp afterwards in following 8 hours at 120 ℃.50-60 ℃/60mmHg cut is collected in aftertreatment and rectifying.Hexamethylene diisocyanate content 89% (HPLC) wherein, NCO content 41.5wt% (theoretical value 50wt%), HCl content 0.67wt%, toluene level 0.22wt%.
Embodiment 5:
Hexamethylene diisocyanate:
Except that temperature of reaction changes into 140 ℃, other reaction conditionss are with embodiment 4.Obtain hexamethylene diisocyanate content 95% (HPLC) in the product, NCO content 48.8wt% (theoretical value 50wt%), HCl content 0.17wt%, toluene level 0.06wt%.
Embodiment 6:
1,2,4-benzene triisocyanate:
232.5g (1mol) 1,2,400ml cyanobenzene solution, the 594g (2mol) of 4-benzene three amine hydrochlorates be two-and the 1000ml cyanobenzene solution of (trichloromethyl) carbonic ether is added drop-wise in the 100ml cyanobenzene by the method among the embodiment 1,160 ℃ add in following 8 hours, insulation 3 hours under uniform temp afterwards.110-120 ℃/2mmHg cut is collected in aftertreatment and rectifying.Wherein 1,2,4-benzene triisocyanate content 83.2% (HPLC), NCO content 49.3wt% (theoretical value 62.7wt%), HCl content 0.84wt%, cyanobenzene content 1.2wt%.
Embodiment 7:
1,2,4-benzene triisocyanate:
Except that the dropping time changes 10 hours into, dropwise the back soaking time and change into outside 2 hours, other reaction conditionss are with embodiment 6.Obtain in the product 1,2,4-benzene content 85% (HPLC), NCO content 52.4wt% (theoretical value 62.7wt%), HCl content 0.81wt%, cyanobenzene content 1.3wt%.
Claims (5)
1. one kind prepares the method for polyisocyanates with solid phosgene, and it is characterized in that: with solid phosgene and polyamines and/or its reactant salt, make polyisocyanates, its step is as follows:
(1) solid phosgene, polyamines and/or its salt are dissolved in respectively in the inert solvent, obtain solid phosgene solution, polyamines and/or its salts solution respectively;
(2) under 100-200 ℃, solid phosgene solution and polyamines and/or its salts solution are added drop-wise in the reactor, react;
(3) vacuum fractionation obtains polyisocyanates.
2. as claimed in claim 1ly prepare the method for polyisocyanates, it is characterized in that: polyamines and/or its salt that described polyamines and/or its salt are selected from fat polyamine and/or its salt, aromatic multi-amine and/or its salt, are obtained by the amino acid esterification with solid phosgene.
3. as each described method for preparing polyisocyanates with solid phosgene among the claim 1-2, it is characterized in that: described polyamines and/or its salt are selected from: quadrol, 1, the 6-hexanediamine, 1, the 4-butanediamine, 1, the 4-pentamethylene diamine, 1,2, the 6-hexanediamine, 1,3, the 6-heptamethylene diamine, 1, the 4-diamino-cyclohexane, 1, the 3-diamino-cyclohexane, adjacent dibenzylamine, between dibenzylamine, to dibenzylamine, 2-(beta-aminoethyl) benzylamine, 2, the 4-tolylene diamine, 2, the 5-tolylene diamine, 1,2,4-benzene triamine, or the reaction of amino acid and the thanomin diamines or the triamine that obtain, or the hydrochloric acid of above-mentioned amine, sulfuric acid, phosphoric acid or nitrate.
4. as each describedly prepares the method for polyisocyanates with solid phosgene among the claim 1-2, it is characterized in that: described inert solvent is aromatic hydrocarbon, halogenated aryl hydrocarbon, benzene nitrile, aliphatic ester or aromatic ester class.
5. as each describedly prepares the method for polyisocyanates with solid phosgene among the claim 1-2, it is characterized in that: the mol ratio of described polyamines and/or its salt and solid phosgene is 1: 1-1: 20.
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| CNB200510008982XA CN100366607C (en) | 2005-02-28 | 2005-02-28 | Process for preparing polyisocyanate by solid phosgene |
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| CNB200510008982XA CN100366607C (en) | 2005-02-28 | 2005-02-28 | Process for preparing polyisocyanate by solid phosgene |
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| CN100366607C true CN100366607C (en) | 2008-02-06 |
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| CN101265236B (en) * | 2008-04-28 | 2012-05-23 | 武穴市龙翔药业有限公司 | Synthesis technique for toltrazuril |
| CN102093259A (en) * | 2010-12-23 | 2011-06-15 | 浙江丽水有邦化工有限公司 | Method for preparing 4,4'-dicyclohexyl methane diisocyanate |
| CN103553969B (en) * | 2010-12-23 | 2015-05-27 | 浙江丽水有邦新材料有限公司 | Preparation method of 4,4'-dicyclohexylmethane diisocyanate |
| CN102086162A (en) * | 2010-12-23 | 2011-06-08 | 浙江丽水有邦化工有限公司 | Method for preparing methylcyclohexyl diisocyanate |
| CN102659631B (en) * | 2011-12-24 | 2014-05-07 | 德州绿邦化工有限公司 | One-step synthesis of ethyl isocyanate |
| CN102617401A (en) * | 2012-03-08 | 2012-08-01 | 象山志华新材料有限公司 | Synthesis method for co-producing p-chloroaniline and p-chlorophenol isocyanate |
| CN102827035A (en) * | 2012-08-21 | 2012-12-19 | 江苏恒祥化工有限责任公司 | 1, 4-cyclohexyl diisocyanate synthesis method |
| CN103351312A (en) * | 2013-07-01 | 2013-10-16 | 太仓市恒益医药化工原料厂 | Preparation process for 1,4-phenylene diisocyanate |
| CN104529874B (en) * | 2014-12-15 | 2017-04-12 | 绍兴瑞康生物科技有限公司 | Method for preparing urea bonded multifunctional synergic anti-oxidation stabilizer |
| CN106045882A (en) * | 2016-06-03 | 2016-10-26 | 山东崇舜化工有限公司 | Method for synthesizing pentamethylene diisocyanate |
| CN106883150A (en) * | 2017-01-25 | 2017-06-23 | 南京工业大学 | A kind of method of the diisocyanate of synthesising biological base 1,5 penta |
| CN108484447A (en) * | 2018-05-28 | 2018-09-04 | 江阴市万丰化工物资有限公司 | The synthetic method of m-xylylene diisocyanate |
| CN111662214A (en) * | 2020-06-24 | 2020-09-15 | 江苏蓝丰生物化工股份有限公司 | Method for preparing cyclohexyl isocyanate by using solid phosgene |
| US20230374194A1 (en) * | 2020-12-01 | 2023-11-23 | Wanhua Chemical Group Co., Ltd | Polyisocyanate composition, preparation method therefor and application thereof |
| CN115594612A (en) * | 2022-09-19 | 2023-01-13 | 西安近代化学研究所（Cn） | Synthetic method and application of fluorotoluene diisocyanate |
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