JPH01125359A - Production of isocyanates - Google Patents
Production of isocyanatesInfo
- Publication number
- JPH01125359A JPH01125359A JP28444287A JP28444287A JPH01125359A JP H01125359 A JPH01125359 A JP H01125359A JP 28444287 A JP28444287 A JP 28444287A JP 28444287 A JP28444287 A JP 28444287A JP H01125359 A JPH01125359 A JP H01125359A
- Authority
- JP
- Japan
- Prior art keywords
- phosphite
- isocyanate
- carbamate
- pyrolysis
- reaction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000012948 isocyanate Substances 0.000 title claims abstract description 19
- 150000002513 isocyanates Chemical class 0.000 title claims abstract description 19
- 238000004519 manufacturing process Methods 0.000 title claims description 12
- -1 carbamate ester Chemical class 0.000 claims abstract description 15
- 238000000034 method Methods 0.000 claims description 6
- 238000005979 thermal decomposition reaction Methods 0.000 claims description 5
- 150000004657 carbamic acid derivatives Chemical class 0.000 claims description 4
- 239000000126 substance Substances 0.000 abstract description 3
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 abstract description 2
- 238000009825 accumulation Methods 0.000 abstract description 2
- 125000002723 alicyclic group Chemical group 0.000 abstract description 2
- 125000001931 aliphatic group Chemical group 0.000 abstract description 2
- 150000001875 compounds Chemical class 0.000 abstract description 2
- XTTGYFREQJCEML-UHFFFAOYSA-N tributyl phosphite Chemical compound CCCCOP(OCCCC)OCCCC XTTGYFREQJCEML-UHFFFAOYSA-N 0.000 abstract description 2
- BDZBKCUKTQZUTL-UHFFFAOYSA-N triethyl phosphite Chemical compound CCOP(OCC)OCC BDZBKCUKTQZUTL-UHFFFAOYSA-N 0.000 abstract description 2
- 238000000197 pyrolysis Methods 0.000 abstract 3
- GTCAXTIRRLKXRU-UHFFFAOYSA-N methyl carbamate Chemical compound COC(N)=O GTCAXTIRRLKXRU-UHFFFAOYSA-N 0.000 abstract 2
- KXDHJXZQYSOELW-UHFFFAOYSA-M Carbamate Chemical compound NC([O-])=O KXDHJXZQYSOELW-UHFFFAOYSA-M 0.000 abstract 1
- 229920000642 polymer Polymers 0.000 abstract 1
- 238000006243 chemical reaction Methods 0.000 description 13
- 239000003381 stabilizer Substances 0.000 description 7
- 150000002148 esters Chemical class 0.000 description 6
- HVLLSGMXQDNUAL-UHFFFAOYSA-N triphenyl phosphite Chemical compound C=1C=CC=CC=1OP(OC=1C=CC=CC=1)OC1=CC=CC=C1 HVLLSGMXQDNUAL-UHFFFAOYSA-N 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- 239000005058 Isophorone diisocyanate Substances 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- NIMLQBUJDJZYEJ-UHFFFAOYSA-N isophorone diisocyanate Chemical compound CC1(C)CC(N=C=O)CC(C)(CN=C=O)C1 NIMLQBUJDJZYEJ-UHFFFAOYSA-N 0.000 description 4
- YGYAWVDWMABLBF-UHFFFAOYSA-N Phosgene Chemical compound ClC(Cl)=O YGYAWVDWMABLBF-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 125000005442 diisocyanate group Chemical group 0.000 description 3
- 238000004821 distillation Methods 0.000 description 3
- 125000000962 organic group Chemical group 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- KXDHJXZQYSOELW-UHFFFAOYSA-N Carbamic acid Chemical group NC(O)=O KXDHJXZQYSOELW-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000004817 gas chromatography Methods 0.000 description 2
- IQPQWNKOIGAROB-UHFFFAOYSA-N isocyanate group Chemical group [N-]=C=O IQPQWNKOIGAROB-UHFFFAOYSA-N 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- YCWSUKQGVSGXJO-NTUHNPAUSA-N nifuroxazide Chemical group C1=CC(O)=CC=C1C(=O)N\N=C\C1=CC=C([N+]([O-])=O)O1 YCWSUKQGVSGXJO-NTUHNPAUSA-N 0.000 description 2
- OJMIONKXNSYLSR-UHFFFAOYSA-N phosphorous acid Chemical compound OP(O)O OJMIONKXNSYLSR-UHFFFAOYSA-N 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- OHWZQGOJLRVRIW-UHFFFAOYSA-N (3-carbamoyloxy-4-methylphenyl) carbamate Chemical compound CC1=CC=C(OC(N)=O)C=C1OC(N)=O OHWZQGOJLRVRIW-UHFFFAOYSA-N 0.000 description 1
- IGQXORINWHZSBK-UHFFFAOYSA-N 2,3,5,5-tetramethylcyclohex-2-en-1-one Chemical compound CC1=C(C)C(=O)CC(C)(C)C1 IGQXORINWHZSBK-UHFFFAOYSA-N 0.000 description 1
- 125000002252 acyl group Chemical group 0.000 description 1
- 239000003905 agrochemical Substances 0.000 description 1
- 125000003545 alkoxy group Chemical group 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- AQLMHYSWFMLWBS-UHFFFAOYSA-N arsenite(1-) Chemical compound O[As](O)[O-] AQLMHYSWFMLWBS-UHFFFAOYSA-N 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- YUOUKRIPFJKDJY-UHFFFAOYSA-L beryllium;diacetate Chemical compound [Be+2].CC([O-])=O.CC([O-])=O YUOUKRIPFJKDJY-UHFFFAOYSA-L 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000011437 continuous method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 125000001033 ether group Chemical group 0.000 description 1
- 125000004494 ethyl ester group Chemical group 0.000 description 1
- LBKPGNUOUPTQKA-UHFFFAOYSA-N ethyl n-phenylcarbamate Chemical compound CCOC(=O)NC1=CC=CC=C1 LBKPGNUOUPTQKA-UHFFFAOYSA-N 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 125000005843 halogen group Chemical group 0.000 description 1
- 229940127554 medical product Drugs 0.000 description 1
- 150000004702 methyl esters Chemical class 0.000 description 1
- IAGUPODHENSJEZ-UHFFFAOYSA-N methyl n-phenylcarbamate Chemical compound COC(=O)NC1=CC=CC=C1 IAGUPODHENSJEZ-UHFFFAOYSA-N 0.000 description 1
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 description 1
- 150000002989 phenols Chemical class 0.000 description 1
- XVNKRRXASPPECQ-UHFFFAOYSA-N phenyl n-phenylcarbamate Chemical compound C=1C=CC=CC=1OC(=O)NC1=CC=CC=C1 XVNKRRXASPPECQ-UHFFFAOYSA-N 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 150000003459 sulfonic acid esters Chemical class 0.000 description 1
- DVKJHBMWWAPEIU-UHFFFAOYSA-N toluene 2,4-diisocyanate Chemical compound CC1=CC=C(N=C=O)C=C1N=C=O DVKJHBMWWAPEIU-UHFFFAOYSA-N 0.000 description 1
- 125000005628 tolylene group Chemical group 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- FEVFLQDDNUQKRY-UHFFFAOYSA-N tris(4-methylphenyl) phosphite Chemical compound C1=CC(C)=CC=C1OP(OC=1C=CC(C)=CC=1)OC1=CC=C(C)C=C1 FEVFLQDDNUQKRY-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、ウレタンや医療品、農薬などの製造原料とし
て有用なイソシアネートの製造方法に関し、詳しくは、
カルバミン酸エステル類よりイソシアネート類特にジイ
ソシアネート類を製造する方法に関するものである。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for producing isocyanate useful as a raw material for producing urethane, medical products, agricultural chemicals, etc.
The present invention relates to a method for producing isocyanates, particularly diisocyanates, from carbamate esters.
イソシアネート類は、従来より、対応するアミン類とホ
スゲンとの反応によって製造されているが、猛毒性のホ
スゲンを使用すること、および腐食性の塩類を大量に副
生ずることなどから、ホスゲンを用いないでイソシアネ
ートａを製造する方法としてカルバミン酸エステル類の
熱分解法が提案されており、特公昭５７−４５７３６号
公！１（三井東圧）を始めとして、いくつかの例が開示
されている。しかし、この熱分解反応は、一般にその反
応条件が厳しいことから種々の副反応により、イソシア
ネートの収率が低下し易く、特に、工業的に重要なジイ
ソシアネートの製造においては生成したモノイソシアネ
ート・モノカルバメート中間体がさらに反応器中で加熱
されるため、収率低下が著しく、上記特許における開示
例においてもトリレンジカルバメートよりのトリレンジ
イソシアネート収率は９５〜８７％程度に止まっている
。この問題の解決法としては、カルボン酸クロライド、
スルホン酸エステル等のイソシアネートの安定剤を反応
時に添加する方法が示されている（特開昭５７−１２３
１５９号公報、バイエル）が、開示例としては、モノイ
ソシアネートの製造のみが挙げられており、ジイソシア
ネート類の製造にも有効な安定剤は知られていない。Isocyanates have traditionally been produced by reacting the corresponding amines with phosgene, but phosgene is not used because it uses highly toxic phosgene and produces a large amount of corrosive salts as a by-product. A method of thermal decomposition of carbamate esters has been proposed as a method for producing isocyanate a, as disclosed in Japanese Patent Publication No. 57-45736! Several examples have been disclosed, including 1 (Mitsui Toatsu). However, since this thermal decomposition reaction generally requires severe reaction conditions, the yield of isocyanate tends to decrease due to various side reactions. In particular, in the production of industrially important diisocyanates, the produced monoisocyanate/monocarbamate Since the intermediate is further heated in the reactor, the yield decreases significantly, and even in the example disclosed in the above patent, the yield of tolylene diisocyanate from tolylene dicarbamate remains at about 95 to 87%. As a solution to this problem, carboxylic acid chloride,
A method of adding an isocyanate stabilizer such as a sulfonic acid ester during the reaction is disclosed (Japanese Patent Application Laid-Open No. 57-123
No. 159 (Bayer) discloses only the production of monoisocyanates, and no stabilizer is known that is also effective for the production of diisocyanates.
上記の問題点を克服するため、本発明者らは、カルバミ
ン酸エステルの熱分解によるイソシアネートの生成反応
における副反応、就中、生成物のイソシアネートの重合
等による収率低下を防止する目的で、種々の安定剤の存
在下で熱分解反応を検討した結果、亜リン酸トリエステ
ルの添加が、イソシアネート収率の向上に極めて有効で
ある事を見出し、カルバミン酸エステル類から、イソシ
アネート類を収率良く製造する本発明に至ったものであ
る。In order to overcome the above-mentioned problems, the present inventors have aimed at preventing side reactions in the isocyanate production reaction by thermal decomposition of carbamate esters, in particular, a decrease in yield due to polymerization of the product isocyanate, etc. As a result of examining thermal decomposition reactions in the presence of various stabilizers, we found that the addition of phosphorous triester is extremely effective in improving the isocyanate yield, and we have found that the addition of phosphorous triester is extremely effective in improving the yield of isocyanates from carbamate esters. This led to the present invention, which can be easily manufactured.
以下、本発明を具体的に説明する。The present invention will be explained in detail below.
（原料）
本発明において、原料として用いられるカルバミン酸エ
ステルは、一般式
％式％）
で示される化合物である。ここでＲは、飽和または不飽
和の脂肪族基、脂環族基、芳香族基から選ばれた有機基
を表わし、Ｒ゛は飽和又は不飽和の脂肪族基、脂環族基
、芳香族基から選ばれた有機基を表わす。これらの有機
基は、イソシアネート基と反応しない他の置換基、例え
ばハロゲン原子、ニトロ基、アルキル基、アルコキシ基
、エーテル基、アシル基、カルボニル基等、あるいはイ
ソシアネート基自身を含んでいてもよい。又、ｎは１〜
４である。このようなカルバミン酸エステルの具体例と
しては例えば、メチルカルバニレート、エチルカルバニ
レート、フェニルカルバニレート、トリルカルバミン酸
のメチルエステル、エチルエステル、フェニルエステル
、トリレンジカルバミン酸のジアルキルエステルまたは
ジアリールエステル、イソホロンジイソシアネートとア
ルコールまたはフェノール類とのジカルバミン酸ジアル
キルエステルまたはジアリールエステル類等が挙げられ
る。(Raw material) In the present invention, the carbamate ester used as a raw material is a compound represented by the general formula %. Here, R represents an organic group selected from a saturated or unsaturated aliphatic group, an alicyclic group, or an aromatic group; Represents an organic group selected from These organic groups may contain other substituents that do not react with the isocyanate group, such as a halogen atom, a nitro group, an alkyl group, an alkoxy group, an ether group, an acyl group, a carbonyl group, or the isocyanate group itself. Also, n is 1~
It is 4. Specific examples of such carbamate esters include, for example, methyl carbanilate, ethyl carbanilate, phenyl carbanilate, methyl ester, ethyl ester, phenyl ester of tolylcarbamic acid, dialkyl ester or diaryl of tolylene dicarbamic acid. Examples include esters, dicarbamic acid dialkyl esters or diaryl esters of isophorone diisocyanate and alcohol or phenols.
（反応形態）
本発明の反応方法は、回分法でも連続法でもよい。−船
釣な装置としては、反応器とそれに付属した、蒸留装置
があれば良く、反応器で発生するガスを蒸留分離カラム
に導き、未反応物は凝縮液として反応器に戻し、生成す
るイソシアネートおよびアルコールを選択的に分離でき
るものが好適に使用される。(Reaction Form) The reaction method of the present invention may be a batch method or a continuous method. - As a boat fishing device, it is sufficient to have a reactor and a distillation device attached to it, and the gas generated in the reactor is guided to a distillation separation column, unreacted substances are returned to the reactor as a condensate, and the isocyanate produced is Those that can selectively separate alcohol and alcohol are preferably used.
反応温度は、原料のカルバミン酸エステルの分解されや
すさ、および沸点に応じて、１００〜３５０℃の範囲内
から、より好ましくは、１８０〜３００℃の範囲内から
選ばれる。The reaction temperature is selected from the range of 100 to 350°C, more preferably from the range of 180 to 300°C, depending on the ease of decomposition and boiling point of the raw material carbamate ester.
反応器内の圧力については、生成するイソシアネートお
よびアルコールの沸点が、前記の反応温度以下となるよ
う、即ち、イソシアネートおよびアルコールが生成後直
ちに、反応器より留出するような圧力が好適に選ばれる
。The pressure in the reactor is preferably selected so that the boiling point of the isocyanate and alcohol produced is below the reaction temperature, that is, the pressure is such that the isocyanate and alcohol are immediately distilled from the reactor after being produced. .
また、触媒の使用は、分解温度を下げたり、反応速度を
高めるのに有効であるが、必ずしも本発明の必須要件で
はない。Furthermore, although the use of a catalyst is effective for lowering the decomposition temperature and increasing the reaction rate, it is not necessarily an essential requirement of the present invention.
（安定剤）
本発明においては、イソシアネート類の収率を向上させ
るため、安定剤として、亜リン酸トリエステル類を反応
時に添加する。亜リン酸トリエステルの具体例としては
、亜リン酸トリエチル、亜リン酸トリブチル等の亜リン
酸トリアルキルエステル、亜リン酸トリフェニル、亜リ
ン酸トリトリル等の亜リン酸トリアリールエステル等が
挙げられる。中でも亜すン酸トリフェ 。(Stabilizer) In the present invention, in order to improve the yield of isocyanates, phosphorous triesters are added as a stabilizer during the reaction. Specific examples of phosphite triesters include phosphite trialkyl esters such as triethyl phosphite and tributyl phosphite, and phosphite triaryl esters such as triphenyl phosphite and tritolyl phosphite. It will be done. Among them, arsenite tripe.
ニル等の高沸点のエステルが、反応中の揮散が少なく、
有利である。また添加量は、あまり多い場合、イソシア
ネートの生成をも阻害するため、一般に、原料のカルバ
ミン酸エステルに対し、モル比で１ ／１００以下１
／１０００以上が好ましい。High boiling point esters such as
It's advantageous. In addition, if the amount added is too large, it will inhibit the production of isocyanate, so it is generally 1/100 or less in molar ratio to the raw material carbamate ester.
/1000 or more is preferable.
本発明の方法によれば、生成物の重合等による収率低下
が抑制されるとともに、重合物の蓄積がほとんどないの
で長期間の連続運転が可能である。According to the method of the present invention, a decrease in yield due to product polymerization, etc. is suppressed, and since there is almost no accumulation of polymerized products, continuous operation for a long period of time is possible.
以下実施例により本発明を説明するが、本発明はこれら
の実施例に限定されるものではない。The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.
実施例１
２０段オールダーショー蒸留塔を備えたガラス製反応器
にイソホロンジ力ルバミン酸メチル５０．０ｇおよび触
媒として酢酸ベリリウムＯ，Ｉｇ、安定剤として、亜リ
ン酸トリフェニルＯ，１ｇを仕込み、反応温度２２０〜
２３０°Ｃ１圧５ Ｔｏｒｒで、生成するイソホロンジ
イソシアネート及びメクノールを別々に留出させながら
、２時間反応させた。反応後の留出液および缶液をガス
クロ分析した結果、イソホロンジイソシアネート３８．
０ｇの生成が確認された（収率９８％）。Example 1 A glass reactor equipped with a 20-stage Oldershaw distillation column was charged with 50.0 g of methyl isophorone dihydrolbamate, beryllium acetate O, Ig as a catalyst, and triphenyl phosphite O, 1 g as a stabilizer, Reaction temperature 220~
The reaction was carried out at 230° C. and a pressure of 5 Torr for 2 hours while separately distilling the produced isophorone diisocyanate and mechnol. Gas chromatography analysis of the distillate and bottom liquid after the reaction revealed that isophorone diisocyanate was 38.
Production of 0 g was confirmed (yield 98%).
比較例１
安定剤として亜リン酸トリフェニルを使用しなかった他
は、実施例１と全く同様にイソホロンジカルバミン酸メ
チルの熱分解を行った。反応後の留出液および缶液をガ
スクロ分析した結果イソホロンジイソシアネー）３４．
９ｇの生成が確認された（収率９０％）。Comparative Example 1 Methyl isophoronedicarbamate was thermally decomposed in exactly the same manner as in Example 1, except that triphenyl phosphite was not used as a stabilizer. Gas chromatography analysis of the distillate and bottom liquid after the reaction revealed isophorone diisocyanate) 34.
Production of 9 g was confirmed (yield 90%).
Claims (1)
アネート類を製造する方法において、亜リン酸トリエス
テル類の存在下で熱分解させることを特徴とするイソシ
アネート類の製造法。1. A method for producing isocyanates by thermally decomposing carbamate esters to produce corresponding isocyanates, the method comprising carrying out the thermal decomposition in the presence of phosphite triesters.
Priority Applications (7)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28444287A JPH01125359A (en) | 1987-11-11 | 1987-11-11 | Production of isocyanates |
| PCT/JP1988/000026 WO1988005430A1 (en) | 1987-01-13 | 1988-01-13 | Process for preparing isocyanate compounds |
| DE3850647T DE3850647T2 (en) | 1987-01-13 | 1988-01-13 | METHOD FOR PRODUCING ISOCYANATE COMPOUNDS. |
| EP88900845A EP0323514B1 (en) | 1987-01-13 | 1988-01-13 | Process for preparing isocyanate compounds |
| US08/358,680 US5773643A (en) | 1987-01-13 | 1994-12-19 | Process for preparation of isocyanate compounds |
| US08/560,517 US5914428A (en) | 1987-01-13 | 1995-11-16 | Process for preparation of isocyanate compounds |
| US08/940,364 US5789614A (en) | 1987-01-13 | 1997-09-30 | Process for preparation of aliphatic diisocyanate compounds |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28444287A JPH01125359A (en) | 1987-11-11 | 1987-11-11 | Production of isocyanates |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01125359A true JPH01125359A (en) | 1989-05-17 |
Family
ID=17678596
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28444287A Pending JPH01125359A (en) | 1987-01-13 | 1987-11-11 | Production of isocyanates |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01125359A (en) |
-
1987
- 1987-11-11 JP JP28444287A patent/JPH01125359A/en active Pending
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