CA1117976A - Simultaneous preparation of 1,3-disubstituted ureas and 1,2-diols - Google Patents
Simultaneous preparation of 1,3-disubstituted ureas and 1,2-diolsInfo
- Publication number
- CA1117976A CA1117976A CA000316802A CA316802A CA1117976A CA 1117976 A CA1117976 A CA 1117976A CA 000316802 A CA000316802 A CA 000316802A CA 316802 A CA316802 A CA 316802A CA 1117976 A CA1117976 A CA 1117976A
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- starting material
- reaction
- tion
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- ureas
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-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/18—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas
- C07C273/1809—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of substituted ureas with formation of the N-C(O)-N moiety
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- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Abstract of the Disclosure: 1,3-Disubstituted ureas and 1,2-diols are prepared simultaneously by reacting cyclic carbonates with amines in a particular ratio, at an elevated temperature.
The ureas I obtainable by the process of the inven-tion are valuable starting materials for the synthesis of dyes and crop protection agents.
The ureas I obtainable by the process of the inven-tion are valuable starting materials for the synthesis of dyes and crop protection agents.
Description
~IL7~71~;
, O.Z. 0050/~2944 Simultaneous preparation of l,~-disubstitu-ted ureas and 1,2-diols . ~
The present invention relates to a process for the simultaneous preparation of 1,3 disubstituted ureas and 1,2-diols by reacting cyclic carbonates with amines in ~ a particular ratio atanelevated temperature~
- Glycols, eg. ethylene glycol, may be prepared, for example, by alkaline hydrolysis of dichloro compoundsor of . ., chlorohydrins, eg. ethylene chlorohydrin or 1,2-dichloro-ethane (Ullmanns Encyclopadie der technischen Chemie,4th edition, volume 8, page 201). However, the highly corrosive properties of such reaction mixtures have made it difficult to handle them in industrial plant. Recently, the acid-catalyzed hydrolysis of ethylene oxide has there-` fore also acquired substantial industrial importance.
Disadvantages of this reaction are the competing formation of polyglycols, and the highly exothermic nature of the ring scission.
Amongst industrially important processes for the preparation of ureas, the reaction of isocyanates, carbamic acid chlorides or phosgene with amines should be singled out particularly (Ullmann, 3rd edition, volume 8, page 390).
Its disadvantage is that very toxic materials which pollute the environmen-t, for example phosgene and hydrochloric acid, have to be handled. Furthermore~ the exothermicity of the reaction can only be controlled with difficulty on an ` indus-trial scale and the ureas formed are contaminated with saline compounds. The trans-amidation of urea requires a very high excess of amines to give satisfactory yields;
3'76 ; O.Z. 0050/032941~
because an equi]ibrium exists, the end products are always contaminated with varying amounts of monosubsti-tuted ureas.
A further disadvantage is that gaseous ammonia is liberated and must either be burnt or be bonded by neutralizing it with aqueous hydrochloric acidO
All the above processes are therefore unsatis-factory for industrial operation, from the point of view of economics and of non-pollution of the environment.
`; French Patent 1,096,Z04 discloses that the reaction lG of alkylene carbonates with amines does not result in 2 fragments, namely the substituted urea and the glycol, but that the ring opens to form only ~ substituted carbamate, for example ~-hydroxyethyl carbamate. Furthermore, this carbamate formation is independent of the amount of amine employed; even with excess amine, as recommended in the ., said patent, ureas are not obtained. Moreover, this method requires that low temperatures (from 0 to 50C) are maintained if satisfactory yields are to be achieved.
If water is used, the reaction must be carried out at from ; 20 0 to 10C, since otherwise the amine exerts a hydrolyzing action, for example like an alkali, and causes glycol and amine, but no urea, to be formed.
;~ The sensitivity of the said carbamates is also des-cribed in an article in Bull. Soc. C~lim. France (volume 1956, pages 831 - 836), which states that ~-hydroxyethyl carbamates cannot be distilled even under reduced pressure.
The decomposition products obtained from 2 molecules of ' ~-hydroxyethyl carbamate are glycol, carbon dioxide, ethy-lene oxide and 1 molecule o urea.
``~
L7~76 . O.Z. 0050/032944 In the case of aromatic amines, the reaction with ethylene carbonate leads, depending on the temperature range, to decarboxylation and the production of hydro~y-ethylamines (150 - 190C) or the production of 3-aryloxa-zolid-2-ones (180 - 200), as shown by recent work by E. Gulbins and K. Hamann (Chem. Ber., 99 (1966), 55 - 61).
We have found that 1,3-disubstituted ureas of -the formula .
- H O H
Rl _ N - C - N - Rl I
where Rl is an aliphatic, cycloaliphatic or araliphatic -~ 10 radical,and 1,2-diols of the formula - R2 _ C - C - R2 II
, .OH OH
where the individual radicals R2 and R3 are identical or ` different and each is hydrogen or an aliphatic radical, and ; the two radicals R3 together with the two adjacent carbon atoms can also be members of a ring, are obtained simul-~` taneously and advantageously when cyclic, aliphatic carbonates of the formula " , ~Cj : 2 1 ~ 2 ;I R -C --C~R III
where R2 and R3 have the above meaningS, are reacted with amines of the formula Rl _ NH2 IV
where Rl has the above meaning, in a ratio of from 2 to 20 : - . .
` ";
~79~
- O~Z. 0050/0~2944 ~ moles of starting material IV per mole of starting material -~ III at above 100C.
Where ethylene carbonate and n-propylamine are used, the reaction can be represented by the following equation:
:' O
': C
-.: / \
; l 3 7 2 ~~~~~~~~~----3 ` H2C--CH2 O
:. "
: n c3 H7-NH-c-NH-n-c3H7 + HO-CH2CH2 ,;~ OH
` Compared to the conventional processes, the process .:
of the invention gives 1,3-disubstituted ureas and 1,2-diols simultaneously, by a simplerand more economical method, in ` good yield and high purity, and hence, overall, with a ;~ better space-time yield. The reaction time is in general ` 10 short and the working-up of the reaction mixture is simpler `
and safer, particularly -- from the aspect of protectlon of the environment. All these advantageous results are surprlsing in view of the prior art. In particular, it was to be expected that the temperatures and amounts of ` amine used according to the invention would not permit the formation of ureas or would, at the very least, give hetero-geheous mixtures of decomposition and condensation products, as well as scission products of the cyclic carbonate.
` Preferred star-ting materials III and IV and accord-ingly preferred end products I and II are those where R is alkyl of 1 to 20, especially of 1 to 8, carbon atoms, mono-cycloalkyl of 3 to 8 carbon atoms, bicycloalkyl of 6 to 12 O.Z. ~050/0~944 carbon atoms, aralkyl of 7 to 20, especially of 7 to 12, carbon atoms, or alkyl of 1 -to 20, preferably of 2 to 20, especially of 2 to 8, carbon atoms, which is substituted by a plurality of phenoxy groups or especially by one phen-oxy group and/or by a plurality of alkoxy groups or especially by one alkoxy group of 1 to 13 carbon atoms, the ; individual radicals R2 and R3 may be identical or di~ferent and each is hydrogen or alkyl of 1 to 5 carbon atoms, and the two radicals R3 can also, together with the two adja-cent carbon atoms, be members of a cycloaliphatic ring, especially a cycloalkyl ring of 5 to 8 carbon atoms. The above radicals and rings can also be substituted by groups whiGh are inert under the reaction conditions, eg. alkyl or alkoxy each of 1 to 4 carbon atoms.
` Preferred startLng materials III are ethylene car-bonate, propylene carbonate, 1,2-butylene carbonate,
, O.Z. 0050/~2944 Simultaneous preparation of l,~-disubstitu-ted ureas and 1,2-diols . ~
The present invention relates to a process for the simultaneous preparation of 1,3 disubstituted ureas and 1,2-diols by reacting cyclic carbonates with amines in ~ a particular ratio atanelevated temperature~
- Glycols, eg. ethylene glycol, may be prepared, for example, by alkaline hydrolysis of dichloro compoundsor of . ., chlorohydrins, eg. ethylene chlorohydrin or 1,2-dichloro-ethane (Ullmanns Encyclopadie der technischen Chemie,4th edition, volume 8, page 201). However, the highly corrosive properties of such reaction mixtures have made it difficult to handle them in industrial plant. Recently, the acid-catalyzed hydrolysis of ethylene oxide has there-` fore also acquired substantial industrial importance.
Disadvantages of this reaction are the competing formation of polyglycols, and the highly exothermic nature of the ring scission.
Amongst industrially important processes for the preparation of ureas, the reaction of isocyanates, carbamic acid chlorides or phosgene with amines should be singled out particularly (Ullmann, 3rd edition, volume 8, page 390).
Its disadvantage is that very toxic materials which pollute the environmen-t, for example phosgene and hydrochloric acid, have to be handled. Furthermore~ the exothermicity of the reaction can only be controlled with difficulty on an ` indus-trial scale and the ureas formed are contaminated with saline compounds. The trans-amidation of urea requires a very high excess of amines to give satisfactory yields;
3'76 ; O.Z. 0050/032941~
because an equi]ibrium exists, the end products are always contaminated with varying amounts of monosubsti-tuted ureas.
A further disadvantage is that gaseous ammonia is liberated and must either be burnt or be bonded by neutralizing it with aqueous hydrochloric acidO
All the above processes are therefore unsatis-factory for industrial operation, from the point of view of economics and of non-pollution of the environment.
`; French Patent 1,096,Z04 discloses that the reaction lG of alkylene carbonates with amines does not result in 2 fragments, namely the substituted urea and the glycol, but that the ring opens to form only ~ substituted carbamate, for example ~-hydroxyethyl carbamate. Furthermore, this carbamate formation is independent of the amount of amine employed; even with excess amine, as recommended in the ., said patent, ureas are not obtained. Moreover, this method requires that low temperatures (from 0 to 50C) are maintained if satisfactory yields are to be achieved.
If water is used, the reaction must be carried out at from ; 20 0 to 10C, since otherwise the amine exerts a hydrolyzing action, for example like an alkali, and causes glycol and amine, but no urea, to be formed.
;~ The sensitivity of the said carbamates is also des-cribed in an article in Bull. Soc. C~lim. France (volume 1956, pages 831 - 836), which states that ~-hydroxyethyl carbamates cannot be distilled even under reduced pressure.
The decomposition products obtained from 2 molecules of ' ~-hydroxyethyl carbamate are glycol, carbon dioxide, ethy-lene oxide and 1 molecule o urea.
``~
L7~76 . O.Z. 0050/032944 In the case of aromatic amines, the reaction with ethylene carbonate leads, depending on the temperature range, to decarboxylation and the production of hydro~y-ethylamines (150 - 190C) or the production of 3-aryloxa-zolid-2-ones (180 - 200), as shown by recent work by E. Gulbins and K. Hamann (Chem. Ber., 99 (1966), 55 - 61).
We have found that 1,3-disubstituted ureas of -the formula .
- H O H
Rl _ N - C - N - Rl I
where Rl is an aliphatic, cycloaliphatic or araliphatic -~ 10 radical,and 1,2-diols of the formula - R2 _ C - C - R2 II
, .OH OH
where the individual radicals R2 and R3 are identical or ` different and each is hydrogen or an aliphatic radical, and ; the two radicals R3 together with the two adjacent carbon atoms can also be members of a ring, are obtained simul-~` taneously and advantageously when cyclic, aliphatic carbonates of the formula " , ~Cj : 2 1 ~ 2 ;I R -C --C~R III
where R2 and R3 have the above meaningS, are reacted with amines of the formula Rl _ NH2 IV
where Rl has the above meaning, in a ratio of from 2 to 20 : - . .
` ";
~79~
- O~Z. 0050/0~2944 ~ moles of starting material IV per mole of starting material -~ III at above 100C.
Where ethylene carbonate and n-propylamine are used, the reaction can be represented by the following equation:
:' O
': C
-.: / \
; l 3 7 2 ~~~~~~~~~----3 ` H2C--CH2 O
:. "
: n c3 H7-NH-c-NH-n-c3H7 + HO-CH2CH2 ,;~ OH
` Compared to the conventional processes, the process .:
of the invention gives 1,3-disubstituted ureas and 1,2-diols simultaneously, by a simplerand more economical method, in ` good yield and high purity, and hence, overall, with a ;~ better space-time yield. The reaction time is in general ` 10 short and the working-up of the reaction mixture is simpler `
and safer, particularly -- from the aspect of protectlon of the environment. All these advantageous results are surprlsing in view of the prior art. In particular, it was to be expected that the temperatures and amounts of ` amine used according to the invention would not permit the formation of ureas or would, at the very least, give hetero-geheous mixtures of decomposition and condensation products, as well as scission products of the cyclic carbonate.
` Preferred star-ting materials III and IV and accord-ingly preferred end products I and II are those where R is alkyl of 1 to 20, especially of 1 to 8, carbon atoms, mono-cycloalkyl of 3 to 8 carbon atoms, bicycloalkyl of 6 to 12 O.Z. ~050/0~944 carbon atoms, aralkyl of 7 to 20, especially of 7 to 12, carbon atoms, or alkyl of 1 -to 20, preferably of 2 to 20, especially of 2 to 8, carbon atoms, which is substituted by a plurality of phenoxy groups or especially by one phen-oxy group and/or by a plurality of alkoxy groups or especially by one alkoxy group of 1 to 13 carbon atoms, the ; individual radicals R2 and R3 may be identical or di~ferent and each is hydrogen or alkyl of 1 to 5 carbon atoms, and the two radicals R3 can also, together with the two adja-cent carbon atoms, be members of a cycloaliphatic ring, especially a cycloalkyl ring of 5 to 8 carbon atoms. The above radicals and rings can also be substituted by groups whiGh are inert under the reaction conditions, eg. alkyl or alkoxy each of 1 to 4 carbon atoms.
` Preferred startLng materials III are ethylene car-bonate, propylene carbonate, 1,2-butylene carbonate,
2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-penty-lene carbonate, 3-methyl-1,2-butylene carbonate, 2,2-di-methylethylene carbonate, 2-methyl-2,3-butylene carbonate, 1,2-hexylene carbonate, 2,3-hexylene carbonate, 3,4-hexyl-ene carbonate, cyclopentylene carbonate, cyclohexylene carbonate, cyc~oheptylene carbonate, cyclooctylene carbon-ate, 3-ethyl-~,4-butylene carbonate and 2-methyl-1,2-penty-lene carbonate.
Preferred starting materials IV are methylamine, ethylamine, n-propylamine, isopropylamine, cyclopropylamine, n-butylamine, isobutylamine, sec.-butylamine, tert.-butyl-amine, cyclobutylamine, n-pentylamine, 2-pentylamine,
Preferred starting materials IV are methylamine, ethylamine, n-propylamine, isopropylamine, cyclopropylamine, n-butylamine, isobutylamine, sec.-butylamine, tert.-butyl-amine, cyclobutylamine, n-pentylamine, 2-pentylamine,
3-pentylamine, 3-methyl-2-butylamlne, neopentylamine, _5_ .
, . .
.
1~ 6 o.z. 0050/0,2g4)~
cyclopentylamine, 2-methyl-2-butylami.ne, ~-hexylamine, -` 2~hexylamine, 3-hexylamine, ~-methyl-2-pentylamine, 4-meth-yl-2-pentylamine, 2,2-dimethyl-1-bu-tylamine, 2-methyl-2-pentylamine, cyclohexylamine, n-hep-tylamine, 2-heptylamine, : 3-heptylamine, 4-heptylamine, 3-methyl-2-hexylamine, ~ 4-methyl-2-hexylamine, 5-methyl-2-hexylamine, 2,2-dimethyl-`~ pentylamine, 3,3-dimethyl-2-pentylamine, 2-methyl-2-.,. ~ .
heptylamine, cycloheptylamine, n octylamine~ 2-octylamine, 3-octylamine, 4-octylamine, ~-methyl-2-octylamine, 4-methyl-~: 10 2 -octylamine, 5-methyl-2-octylamine, 2,2-dimethyl-1-hexyl-amine, cyclooctylamine, 3-methyl-2-heptylamine, 4-methyl-` 2-heptylamine, 5-methyl-2-heptylamine, n-nonylamine, - n-decylamine, n-undecylamine, n-dodecylamine, n-tridecyl-amine, n-tetradecylamine, n-pentadecylamine,n-hexadecyl-amine, n-heptadecylamine, n-octadecylamine, n-nonadecyl-amine, eicosylamine, l-methoxy-2-ethylamine, l-methoxy-2-propylamine, 1-methoxy-3~propylamine, 1-methoxy-2-butyl-amine, l-methoxy-3-butylamine, 1-methoxy-4-butylamine, l-methoxy-5-pentylamine, 1-methoxy-6-hexylamine, l-methoxy-~; 20 7-heptylamine, 1-methoxy-8-octylamine, l-methoxy-9-nonyl- ~`
amine, l-methoxy-10-decylamine, 1-ethoxy-2-ethylamine, l-ethoxy-3-propylamine, l-ethoxy-~-butylamlne, l-ethoxy-5-pentylamine, 1-ethoxy-6-hexylamine, 1-ethoxy-7-hept~l-amine, l-ethoxy-8-octylamine, l-ethoxy-9-nonylamine,l-ethoxy-10-decylamine,l-r~propoxy 2- ethylamine, 1-n-butoxy-2- ethyl- ~-amine, l-n- pentoxy-2-ethylamine, l-n- hexoxy-2-ethylamine, l-n-heptoxy-2-ethylamine, 1-n-octoxy-2-e-thylamine, l-n-nonoxy-2-ethylamine, 1-n-decyloxy-2-ethylamine, l-n-undecyloxy-2-ethylamine, 1-dodecyloxy-2-ethylamine, l-tridecyloxy-2-ethylamine, benzylamine, a-methylbenzylamine, 2-phenyl O.Z. 0050/0329~4 ethylamine, 3-phenyl-1-propylamine, 3-phenyl-2-propylamine, 3-phenyl-3-propylamine, 4-phenyl-2-butylamine, l-isopropox~-2-ethylamine, 1-isopropoxy-2-propylamine, l-isopropoxy-3-propylamine, 1-isopropoxy-3-bu-tylamine, l-phenoxy-`~ 2-ethylamine, 1-phenoxy-2-propylamine, 1-phenoxy-3-propyl-amine, l-phenoxy-4-butylamine and 2-norbornylamine.
The starting material III is reacted with the ` starting materialIV in a ratio of ~rom 2 to 20, preferably from 4 to 10, moles of starting material IV per mole of starting material III. The reaction is carried out at above 100Cs advantageously at from 105 to 250C, prefer-ably from 140 to 240C, especially from 170 to 220C, under atmospheric or superatmospheric pressure, continuously or ` batchwise. The amine IV employed can at the same time serve as the solvent for the carbonate III, ~rhich in most cases is crystalline. However, if desired, the reaction can also be carried out in the presence of an organic sol-vent which is inert under the reaction conditions.
Suitable solvents for this purpose are aliphatic, aromatic or araliphatic hydrocarbons, eg. pentane, hexane, cyclo-hexane, heptane, pinane, nonane, o-, m- and p-cymene, gaso line fractions boiling within the range from 70 to 190C, methylcyclohexane, decalin, petroleum ether, naphtha, 2,2,4-trimethylpentane, 2,2,3-trimethylpen-tane, 2,3,3-tri-methylpentane, octane, benzene, toluene, xylene, naphtha-lene and tetralin; ethers,eg. diethyl ether, ethylpropyl ether, methyl-tert.-butyl ether, n-butyl ether, di-n-butyl ether, diisobutyl ether, diisoamyl ether, diisopropyl ether, anisole, phenetole~ cyclohexyl methyl etherj ethylene glycol .
O.Z. 0050/0~2~44 dimethyl ether, tetrahydrofuran, dioxane and thioanisole;
alcohols, eg~ amyl alcohol, n-butanol, sec.-butanol, iso-butanol, tert.-butyl alcohol, isopropanol, n-propanol, ethanol, methanol, glycol, cyclohexanol, heptanol and octanol; and appropria~ce, mixtures. The solvent is advantageously used in an amount of from 50 to 10,000, pre-ferably from 200 to 1,000, percent by weight, based on starting material III.
The reac-tion is carried out as ~ollows: a mixture of starting material III and IV, in the molar ratio accord-ing to the invention, with or withou-t solvent, is reacted for from 0.3 to 6 hours at the reaction temperature. The sequence of addition of the components is optional. In a preferred embodiment of the process according to the invention, a carbonate III is added to an amine IV at room temperature and the reaction is then carried out at the reaction temperature. Because o~ the high vapor pres-sure of low-boiling amines, it is advantageous to mix the . components at room temperature and only to raise the mix-ture to the reaction temperature after the reaction vessel has been closed. In the case of low-molecular weight amines, a pressure vessel must be used. With higher-boiling amines, on the other hand, the reaction can be carried out under atmospheric pressure in an open system or under reflux. In that case, the 1,2-diol II which is formed can also be distilled continuously from the reaction mixture.
I~ suitable devices for metering under pressure are used, it is also possible to mix the starting materials III
~8- , '7l~
. .
.
O.Z. ~50/3294~
and IV directly at -the reaction temperature, and then carry out the reaction. After the reaction, the end products I and II are isolated from the mixture in the conventional manner, for example by filtration and fractional distilla-tion. Advantageously, the mixture is worked up by filtering off the ureas I, which in most cases are in a crystalline form, and fractionally distilling the filtrate.
Depending on the molecular weight, it is usually either the ^: excess starting amine IV or the solvent (if any) which is first obtained as the~low-boiling component during frac-tional distillation; at a higher temperature, the end products IIpass over, and in most cases a small amount of the pure urea I (of which a trace dissolves) remains.
In the case of ureas I obtained as oils, it is advantageous directly to subject the entire reaction mix-ture to fractional distillation; the excess starting amine IV passes over first, followed by the diol II as the higher-boiling component, and the pure urea I remains as a . residue.
However, in the case of water-soluble amines IV, it is also possible to add water to the reaction mixture obtained, fllter off the insoluble urea I, and recover the pure starting amines IV and diols II from the filtrate by fractional distillation.
` The ureas I obtainable by the process of the inven-tion are valuable starting materials for the synthesis of dyes and crop pro-tection agen-ts~ For example, amido-sulfonic acids are obtained from ureas by treatment with -` oleum using the process of British Paten-t 1,185,439 or by 7~
O.Z. 0050/032944 . treatment with sulfur trioxide followed by sulfuric acid, .~
as described in German Laid-Open Applica-tion DOS 2,424,371.
The compounds obtainable b~ these sulfona~ion processes are sweeteners (especially in the case of cyclohexylamidosulfonic acid and its calcium, . sodium and potassium salts) and valuable starting materials for the preparation of sweeteners, dyes and pesticides.
. For example, the corresponding sulfonic acid chlorides, eg~
isopropylaminosulfonyl chloride, can be prepared by chlori-nation, eg. with thionyl chloride; these acid chlorides can then be reacted with anthranilic acid or its salts to give o-sulfamidobenzoic ac.ids. Cyclization of these compounds gives 2,1,3-benzothiadiazin-4-one-2,2-dioxides, the use of which for crop protection agents and drugs is .described in German Laid-Open Application DOS 2,105,687.
Regarding the use of the compounds, reference may be made to the above publication and to German Published Applica-tion DAS 1,120,4569 German Patent 1,242,627 and German Laid-Open Application DOS 1,542,8360 The reaction of .
- - 20 the amidosulfonic acids with halogenating agents by -the -process of U~S. Patent 3;992,444 gives alkylamidosulfonyl halides, the use of which, for the synthesis of dyes and crop protection agents, is described in the same patent;
further possible uses of the compounds, as intermediates for herbicides, are described in German Laid-Open Applica tions DOS 2,201,432 and 2,310,757.
The 1,2-diols II also produced by the process according to the invention are valuable solvents and inter-mediates for the preparation of dyes and crop protection ,-O.Z. OC50/032944 agents. For example, e-thylene glycol is used on a large scale as an anti-freeze ~or internal combustion engine coolan'cs.
They are also starting materials for the preparation of polyester resins, plasticizers, alkyd resins, lubricating oils, hydraulic fluids, polyurethanes and detergent raw materials. Regarding their use, reference may be made to Ullmanns Encyclopadie der technischen Chemie, supple-mentary volume (pages 101 - 103).
In the Examples which follow, parts are by weight.
64.9 parts of ethylene carbonate are introduced into 325 parts of isopropylamine (ie. in a molar ratio of starting material IV to starting material III of 7.5 : 1) in an autoclave at 25 30C, whilst stirring. The mix-ture is then stirred for ~ hours at 180C. It is then cooled, and 94 parts of N,N'-diisopropylurea, of melting point 189 - 190C, are filtered off. The excess iso-propylamine is distilled from the filtrate and the residue is then distilled under reduced pressure. This gives 43.5 parts of glycol of boiling point 46 - 50C/0.01 mm Hg.
5 parts of colorless N,N'-diisopropylurea of melting point 188 - 190C are left as a residue; the total yield of urea is 101 parts (95% of theory).
21 parts of ethylene carbonate are dissolved in 120 parts of isopropylamine (ie. in a molar ratio of starting ma-terial IV to starting material III of 8.5 : 1) at room temperature, whilst stirring. The reaction mixture is :
:
O.Z. 0050/032944 then stirred for 4 hours at 170C, cooled -to ~5~ and freed from excess isopropylamine by distillation. 50 parts of water are now added to the residue and the product is fil-tered off. After drying, ~3.9 parts (98.3% of the-ory) of N,N'-diisopropylurea of melting point 188 - 190C
are obtained.
121.2 parts of 2-phenylethylamine and 18.5 parts of ethylene carbonate (ie. in a molar ratio of starting material IV to starting material III of 4.8 : 1) are intro-duced into a bomb tube and shaken for 3 hours at 190C.
When the reaction mixture has cooled, the product is filtered off, 52.~ parts of N,N'-di-2-phenylethylurea of melting point 134 - 138C being isolated. A further 2 parts of N,N'-di-2~phenylethylurea are obtained by removing the volatile constituents from the filtrate under ; reduced pressure; total yield 54O3 parts (96.2% of theory).
a) 9.7 parts of ethylene carbonate are introduced into 128.7 parts of tridecyloxypropylamine (ie~ in a molar ratio of starting material IV to starting material III of
, . .
.
1~ 6 o.z. 0050/0,2g4)~
cyclopentylamine, 2-methyl-2-butylami.ne, ~-hexylamine, -` 2~hexylamine, 3-hexylamine, ~-methyl-2-pentylamine, 4-meth-yl-2-pentylamine, 2,2-dimethyl-1-bu-tylamine, 2-methyl-2-pentylamine, cyclohexylamine, n-hep-tylamine, 2-heptylamine, : 3-heptylamine, 4-heptylamine, 3-methyl-2-hexylamine, ~ 4-methyl-2-hexylamine, 5-methyl-2-hexylamine, 2,2-dimethyl-`~ pentylamine, 3,3-dimethyl-2-pentylamine, 2-methyl-2-.,. ~ .
heptylamine, cycloheptylamine, n octylamine~ 2-octylamine, 3-octylamine, 4-octylamine, ~-methyl-2-octylamine, 4-methyl-~: 10 2 -octylamine, 5-methyl-2-octylamine, 2,2-dimethyl-1-hexyl-amine, cyclooctylamine, 3-methyl-2-heptylamine, 4-methyl-` 2-heptylamine, 5-methyl-2-heptylamine, n-nonylamine, - n-decylamine, n-undecylamine, n-dodecylamine, n-tridecyl-amine, n-tetradecylamine, n-pentadecylamine,n-hexadecyl-amine, n-heptadecylamine, n-octadecylamine, n-nonadecyl-amine, eicosylamine, l-methoxy-2-ethylamine, l-methoxy-2-propylamine, 1-methoxy-3~propylamine, 1-methoxy-2-butyl-amine, l-methoxy-3-butylamine, 1-methoxy-4-butylamine, l-methoxy-5-pentylamine, 1-methoxy-6-hexylamine, l-methoxy-~; 20 7-heptylamine, 1-methoxy-8-octylamine, l-methoxy-9-nonyl- ~`
amine, l-methoxy-10-decylamine, 1-ethoxy-2-ethylamine, l-ethoxy-3-propylamine, l-ethoxy-~-butylamlne, l-ethoxy-5-pentylamine, 1-ethoxy-6-hexylamine, 1-ethoxy-7-hept~l-amine, l-ethoxy-8-octylamine, l-ethoxy-9-nonylamine,l-ethoxy-10-decylamine,l-r~propoxy 2- ethylamine, 1-n-butoxy-2- ethyl- ~-amine, l-n- pentoxy-2-ethylamine, l-n- hexoxy-2-ethylamine, l-n-heptoxy-2-ethylamine, 1-n-octoxy-2-e-thylamine, l-n-nonoxy-2-ethylamine, 1-n-decyloxy-2-ethylamine, l-n-undecyloxy-2-ethylamine, 1-dodecyloxy-2-ethylamine, l-tridecyloxy-2-ethylamine, benzylamine, a-methylbenzylamine, 2-phenyl O.Z. 0050/0329~4 ethylamine, 3-phenyl-1-propylamine, 3-phenyl-2-propylamine, 3-phenyl-3-propylamine, 4-phenyl-2-butylamine, l-isopropox~-2-ethylamine, 1-isopropoxy-2-propylamine, l-isopropoxy-3-propylamine, 1-isopropoxy-3-bu-tylamine, l-phenoxy-`~ 2-ethylamine, 1-phenoxy-2-propylamine, 1-phenoxy-3-propyl-amine, l-phenoxy-4-butylamine and 2-norbornylamine.
The starting material III is reacted with the ` starting materialIV in a ratio of ~rom 2 to 20, preferably from 4 to 10, moles of starting material IV per mole of starting material III. The reaction is carried out at above 100Cs advantageously at from 105 to 250C, prefer-ably from 140 to 240C, especially from 170 to 220C, under atmospheric or superatmospheric pressure, continuously or ` batchwise. The amine IV employed can at the same time serve as the solvent for the carbonate III, ~rhich in most cases is crystalline. However, if desired, the reaction can also be carried out in the presence of an organic sol-vent which is inert under the reaction conditions.
Suitable solvents for this purpose are aliphatic, aromatic or araliphatic hydrocarbons, eg. pentane, hexane, cyclo-hexane, heptane, pinane, nonane, o-, m- and p-cymene, gaso line fractions boiling within the range from 70 to 190C, methylcyclohexane, decalin, petroleum ether, naphtha, 2,2,4-trimethylpentane, 2,2,3-trimethylpen-tane, 2,3,3-tri-methylpentane, octane, benzene, toluene, xylene, naphtha-lene and tetralin; ethers,eg. diethyl ether, ethylpropyl ether, methyl-tert.-butyl ether, n-butyl ether, di-n-butyl ether, diisobutyl ether, diisoamyl ether, diisopropyl ether, anisole, phenetole~ cyclohexyl methyl etherj ethylene glycol .
O.Z. 0050/0~2~44 dimethyl ether, tetrahydrofuran, dioxane and thioanisole;
alcohols, eg~ amyl alcohol, n-butanol, sec.-butanol, iso-butanol, tert.-butyl alcohol, isopropanol, n-propanol, ethanol, methanol, glycol, cyclohexanol, heptanol and octanol; and appropria~ce, mixtures. The solvent is advantageously used in an amount of from 50 to 10,000, pre-ferably from 200 to 1,000, percent by weight, based on starting material III.
The reac-tion is carried out as ~ollows: a mixture of starting material III and IV, in the molar ratio accord-ing to the invention, with or withou-t solvent, is reacted for from 0.3 to 6 hours at the reaction temperature. The sequence of addition of the components is optional. In a preferred embodiment of the process according to the invention, a carbonate III is added to an amine IV at room temperature and the reaction is then carried out at the reaction temperature. Because o~ the high vapor pres-sure of low-boiling amines, it is advantageous to mix the . components at room temperature and only to raise the mix-ture to the reaction temperature after the reaction vessel has been closed. In the case of low-molecular weight amines, a pressure vessel must be used. With higher-boiling amines, on the other hand, the reaction can be carried out under atmospheric pressure in an open system or under reflux. In that case, the 1,2-diol II which is formed can also be distilled continuously from the reaction mixture.
I~ suitable devices for metering under pressure are used, it is also possible to mix the starting materials III
~8- , '7l~
. .
.
O.Z. ~50/3294~
and IV directly at -the reaction temperature, and then carry out the reaction. After the reaction, the end products I and II are isolated from the mixture in the conventional manner, for example by filtration and fractional distilla-tion. Advantageously, the mixture is worked up by filtering off the ureas I, which in most cases are in a crystalline form, and fractionally distilling the filtrate.
Depending on the molecular weight, it is usually either the ^: excess starting amine IV or the solvent (if any) which is first obtained as the~low-boiling component during frac-tional distillation; at a higher temperature, the end products IIpass over, and in most cases a small amount of the pure urea I (of which a trace dissolves) remains.
In the case of ureas I obtained as oils, it is advantageous directly to subject the entire reaction mix-ture to fractional distillation; the excess starting amine IV passes over first, followed by the diol II as the higher-boiling component, and the pure urea I remains as a . residue.
However, in the case of water-soluble amines IV, it is also possible to add water to the reaction mixture obtained, fllter off the insoluble urea I, and recover the pure starting amines IV and diols II from the filtrate by fractional distillation.
` The ureas I obtainable by the process of the inven-tion are valuable starting materials for the synthesis of dyes and crop pro-tection agen-ts~ For example, amido-sulfonic acids are obtained from ureas by treatment with -` oleum using the process of British Paten-t 1,185,439 or by 7~
O.Z. 0050/032944 . treatment with sulfur trioxide followed by sulfuric acid, .~
as described in German Laid-Open Applica-tion DOS 2,424,371.
The compounds obtainable b~ these sulfona~ion processes are sweeteners (especially in the case of cyclohexylamidosulfonic acid and its calcium, . sodium and potassium salts) and valuable starting materials for the preparation of sweeteners, dyes and pesticides.
. For example, the corresponding sulfonic acid chlorides, eg~
isopropylaminosulfonyl chloride, can be prepared by chlori-nation, eg. with thionyl chloride; these acid chlorides can then be reacted with anthranilic acid or its salts to give o-sulfamidobenzoic ac.ids. Cyclization of these compounds gives 2,1,3-benzothiadiazin-4-one-2,2-dioxides, the use of which for crop protection agents and drugs is .described in German Laid-Open Application DOS 2,105,687.
Regarding the use of the compounds, reference may be made to the above publication and to German Published Applica-tion DAS 1,120,4569 German Patent 1,242,627 and German Laid-Open Application DOS 1,542,8360 The reaction of .
- - 20 the amidosulfonic acids with halogenating agents by -the -process of U~S. Patent 3;992,444 gives alkylamidosulfonyl halides, the use of which, for the synthesis of dyes and crop protection agents, is described in the same patent;
further possible uses of the compounds, as intermediates for herbicides, are described in German Laid-Open Applica tions DOS 2,201,432 and 2,310,757.
The 1,2-diols II also produced by the process according to the invention are valuable solvents and inter-mediates for the preparation of dyes and crop protection ,-O.Z. OC50/032944 agents. For example, e-thylene glycol is used on a large scale as an anti-freeze ~or internal combustion engine coolan'cs.
They are also starting materials for the preparation of polyester resins, plasticizers, alkyd resins, lubricating oils, hydraulic fluids, polyurethanes and detergent raw materials. Regarding their use, reference may be made to Ullmanns Encyclopadie der technischen Chemie, supple-mentary volume (pages 101 - 103).
In the Examples which follow, parts are by weight.
64.9 parts of ethylene carbonate are introduced into 325 parts of isopropylamine (ie. in a molar ratio of starting material IV to starting material III of 7.5 : 1) in an autoclave at 25 30C, whilst stirring. The mix-ture is then stirred for ~ hours at 180C. It is then cooled, and 94 parts of N,N'-diisopropylurea, of melting point 189 - 190C, are filtered off. The excess iso-propylamine is distilled from the filtrate and the residue is then distilled under reduced pressure. This gives 43.5 parts of glycol of boiling point 46 - 50C/0.01 mm Hg.
5 parts of colorless N,N'-diisopropylurea of melting point 188 - 190C are left as a residue; the total yield of urea is 101 parts (95% of theory).
21 parts of ethylene carbonate are dissolved in 120 parts of isopropylamine (ie. in a molar ratio of starting ma-terial IV to starting material III of 8.5 : 1) at room temperature, whilst stirring. The reaction mixture is :
:
O.Z. 0050/032944 then stirred for 4 hours at 170C, cooled -to ~5~ and freed from excess isopropylamine by distillation. 50 parts of water are now added to the residue and the product is fil-tered off. After drying, ~3.9 parts (98.3% of the-ory) of N,N'-diisopropylurea of melting point 188 - 190C
are obtained.
121.2 parts of 2-phenylethylamine and 18.5 parts of ethylene carbonate (ie. in a molar ratio of starting material IV to starting material III of 4.8 : 1) are intro-duced into a bomb tube and shaken for 3 hours at 190C.
When the reaction mixture has cooled, the product is filtered off, 52.~ parts of N,N'-di-2-phenylethylurea of melting point 134 - 138C being isolated. A further 2 parts of N,N'-di-2~phenylethylurea are obtained by removing the volatile constituents from the filtrate under ; reduced pressure; total yield 54O3 parts (96.2% of theory).
a) 9.7 parts of ethylene carbonate are introduced into 128.7 parts of tridecyloxypropylamine (ie~ in a molar ratio of starting material IV to starting material III of
4.5 : 1) whilst stirring at room temperature. After -~ heating for one hour at 200C, the mixture is distilled under reduced pressure, giving 6.52 parts (95.4% of theory3 of glycol and excess amine as the distillate, and a resi-due of 59.4 parts (representing virtually quantitative yield) of N,N'-di-tridecyloxypropylurea as a colorless oil of nD5 = 1.4672.
b) The same yield of N,N'-di-tridecyloxypropylurea~
: "
-' Z . oo50/032g4l~with the same purity, is obtained under the same reaction conditions, but using 100 parts of cyclohexane as the - solvent~
EXAMPLES 5 to 14 The end products listed in the Table are obtained by a method similar to that described in Example 4 a).
: -13-~r o~
, ~ ~ Ln el~ ~Ln ,~ a~ ~cn ~a~ a~a~cn cn a~
..:~ ~ ~
~.~
rl H
. ~H ~ æ
co ~ Ln er ~o Ln ~ ~ ~ ~
O ~ r~D
,1 ~ ~ ~ 1` ~~r a~
.~ o ~ Ln ~ ~ ~g ~ ~ ., o I o I I I I I
. O , ~ Ln o ~~ r-~ ~ ~Ln ~ Ln~ <~
0 0 1~ r~ ~ o ~1 Z
~=o I m V E3 ~ 11 ~ ~ ~ o ~ ~ ~
,lZ ~ X~ y ~ y ~; t) U
U~ CO ~D
o ~ n oo er w
b) The same yield of N,N'-di-tridecyloxypropylurea~
: "
-' Z . oo50/032g4l~with the same purity, is obtained under the same reaction conditions, but using 100 parts of cyclohexane as the - solvent~
EXAMPLES 5 to 14 The end products listed in the Table are obtained by a method similar to that described in Example 4 a).
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O ~ r~D
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. O , ~ Ln o ~~ r-~ ~ ~Ln ~ Ln~ <~
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~=o I m V E3 ~ 11 ~ ~ ~ o ~ ~ ~
,lZ ~ X~ y ~ y ~; t) U
U~ CO ~D
o ~ n oo er w
5~
I` ~ t- ~GO ~ 00 1` ~ Ln P~ ~1 ~ N1~ ~ er ~rer ~ a) o S~ o o o o oo o oo o o u~
O ~ O
I .C
P~ o ~1 ~~r ~~3~er ~ er $r') tr~ ~
.~ -:
, ~ ~ $
I P~ I ^ O
5~ 11 I Lt~
.'~ Z r~ X
Ul ~9 Ln ~o~ 7 ~ Ln r~ ~ ~ I~~ a~ ~1 o a~ o ' er ~0~ OD~J C~l ,J
~J H
H
.
~n a~ Ln rd ~ o ~ r~
.~ ~ .' I ~ Ln ~ ~a~a~ o ~J ~ ~ ~r X
:
.
I` ~ t- ~GO ~ 00 1` ~ Ln P~ ~1 ~ N1~ ~ er ~rer ~ a) o S~ o o o o oo o oo o o u~
O ~ O
I .C
P~ o ~1 ~~r ~~3~er ~ er $r') tr~ ~
.~ -:
, ~ ~ $
I P~ I ^ O
5~ 11 I Lt~
.'~ Z r~ X
Ul ~9 Ln ~o~ 7 ~ Ln r~ ~ ~ I~~ a~ ~1 o a~ o ' er ~0~ OD~J C~l ,J
~J H
H
.
~n a~ Ln rd ~ o ~ r~
.~ ~ .' I ~ Ln ~ ~a~a~ o ~J ~ ~ ~r X
:
.
Claims (6)
1. A process for the simultaneous preparation of 1,3-disubstituted ureas of the formula I
where R1 is an aliphatic, cycloaliphatic or araliphatic radical, and 1,2-diols of the formula II
where the individual radicals R2 and R3 are identical or diff-erent and each is hydrogen or an aliphatic radical, and the two radicals R3 together with the two adjacent carbon atoms can also be members of a ring, wherein cyclic, aliphatic carbon-ates of the formula III
where R2 and R3 have the above meanings, are reacted with amines of the formula where R1 has the above meanings, in a ratio of from 2 to 20 moles of starting material IV per mole of starting material III at above 100°C.
where R1 is an aliphatic, cycloaliphatic or araliphatic radical, and 1,2-diols of the formula II
where the individual radicals R2 and R3 are identical or diff-erent and each is hydrogen or an aliphatic radical, and the two radicals R3 together with the two adjacent carbon atoms can also be members of a ring, wherein cyclic, aliphatic carbon-ates of the formula III
where R2 and R3 have the above meanings, are reacted with amines of the formula where R1 has the above meanings, in a ratio of from 2 to 20 moles of starting material IV per mole of starting material III at above 100°C.
2. A process as claimed in claim 1, wherein the reac-tion is carried out with a ratio of from 4 to 10 moles of starting material IV per mole of starting material III.
3. A process as claimed in claim 1, wherein the O.Z.0050/032944 reaction is carried out at from 105 to 250°C.
4. A process as claimed in claim 1, wherein the reac-tion is carried out at from 140 to 240°C.
5. A process as claimed in claim 1, wherein the reac-tion is carried out at from 170 to 220°C.
6. A process as claimed in claim 1, wherein the reac-tion is carried out in the presence of an organic solvent which is inert under the reaction conditions and is used in an amount of from 50 to 10,000 percent by weight, based on starting material III.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19772756409 DE2756409A1 (en) | 1977-12-17 | 1977-12-17 | Process for the simultaneous preparation of 1,3-disubstituted ureas and 1,2-diols |
| DEP2756409.6 | 1977-12-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1117976A true CA1117976A (en) | 1982-02-09 |
Family
ID=6026464
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000316802A Expired CA1117976A (en) | 1977-12-17 | 1978-11-24 | Simultaneous preparation of 1,3-disubstituted ureas and 1,2-diols |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0002526B1 (en) |
| JP (1) | JPS5490105A (en) |
| CA (1) | CA1117976A (en) |
| DE (2) | DE2756409A1 (en) |
| HU (1) | HU178446B (en) |
| IL (1) | IL56054A0 (en) |
| SU (1) | SU856379A3 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6045540A (en) * | 1983-08-22 | 1985-03-12 | T Hasegawa Co Ltd | Ethylene glycol derivative |
| JPH074349U (en) * | 1993-06-22 | 1995-01-24 | 中国パール販売株式会社 | Packaging bags for food such as sandwiches |
| DE69703019T2 (en) * | 1996-12-05 | 2001-01-11 | Sumika Fine Chemical Co. Ltd., Osaka | Process for the preparation of a 1,3-disubstituted urea |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE848039C (en) * | 1942-12-12 | 1952-09-01 | Boehringer & Soehne Gmbh | Process for the preparation of symmetrical dialkyl ureas |
| GB1452065A (en) * | 1972-11-01 | 1976-10-06 | Ici Ltd | Method for the manufacture of polyurethanes |
-
1977
- 1977-12-17 DE DE19772756409 patent/DE2756409A1/en not_active Withdrawn
-
1978
- 1978-11-24 CA CA000316802A patent/CA1117976A/en not_active Expired
- 1978-11-27 IL IL56054A patent/IL56054A0/en unknown
- 1978-12-12 JP JP15278778A patent/JPS5490105A/en active Granted
- 1978-12-14 DE DE7878101678T patent/DE2861041D1/en not_active Expired
- 1978-12-14 EP EP78101678A patent/EP0002526B1/en not_active Expired
- 1978-12-15 HU HU78BA3741A patent/HU178446B/en unknown
- 1978-12-15 SU SU782700492A patent/SU856379A3/en active
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6217572B2 (en) | 1987-04-18 |
| DE2861041D1 (en) | 1981-11-26 |
| JPS5490105A (en) | 1979-07-17 |
| EP0002526A1 (en) | 1979-06-27 |
| IL56054A0 (en) | 1979-01-31 |
| DE2756409A1 (en) | 1979-06-21 |
| SU856379A3 (en) | 1981-08-15 |
| HU178446B (en) | 1982-05-28 |
| EP0002526B1 (en) | 1981-09-02 |
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