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United States Patent (19) 11) 4,430,505 Heitkämper Et Al

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United States Patent (19) 11) 4,430,505 Heitkämper Et Al United States Patent (19) 11) 4,430,505 Heitkämper et al. (45) Feb. 7, 1984 (54) PROCESS FOR THE PREPARATION OF (56) References Cited N.O-DISUBSTITUTED URETHANES U.S. PATENT DOCUMENTS USEFUL FOR THE PREPARATION OF 2,409,712 10/1946 Schweitzer ... ... 260/453 A ISOCYANATES 2,806,051 9/1957 Brockway...... ... 560/24 75 Inventors: Peter Heitkämper, Dormagen; Klaus 3,627,813 12/1971 Abbate et al. ........................ 560/25 König, Leverkusen; Kurt Findeisen, 4,178,455 12/1979 Hirai et al. ............................ 560/24 Odenthal; Rudolf Fauss, Cologne; 4,388,238 6/1983 Heitkamper et al. ............. 560/22 X Rudolf Sundermann, Leverkusen, all of Fed. Rep. of Germany OTHER PUBLICATIONS 73) Assignee: Bayer Aktiengesellschaft, Adams et al., Chemical Reviews (1965) vol. 65, Leverkusen, Fed. Rep. of Germany 567-572. Primary Examiner-Bernard Helfin (21) Appl. No.: 197,032 Attorney, Agent, or Firm-Gene Harsh; Joseph C. Gil; 22 Filed: Oct. 15, 1980 Lyndanne M. Whalen 30 Foreign Application Priority Data 57 ABSTRACT Oct. 27, 1979 IDE Fed. Rep. of Germany ....... 29.43551 A process for the preparation of N.O-disubstituted ure 51) int. C. ................ C07C 125/065; CO7C 125/073 thanes. Urea or polyurets, primary amines and alcohols (52) U.S. C. ................................... 560/24; 260/465.4; are reacted at 120-350° C. in the presence of N-sub 260/465 D; 260/404; 260/239 E; 260/938; stituted urethanes and/or N-mono- or N,N'-disub 560/22; 560/25; 560/27; 560/28; 560/29; stituted ureas or polyureas. In a preferred embodiment, 560/30; 560/31; 560/32; 560/115; 560/145; the reactants further include catalysts known to be use 560/157; 560/158; 560/160; 560/161; 544/164; ful in esterification of carboxylic acids. The urethanes 544/322; 546/312; 54.6/334; 549/28; 549/467 produced in accordance with this process are particu (58) Field of Search ................ 260/465.4, 465 D, 404, larly useful as starting materials for preparation of iso 260/239 E, 938, 346.7; 560/22, 24, 25, 27, 28, cyanates. 30, 29, 31, 32, 15, 145, 157, 158, 160, 161; 544/164, 322; 54.6/312,334; 549/28; 548/378 15 Claims, No Drawings 4,430,505 1 2 bered heterocyclic radical which, in addition, may PROCESS FOR THE PREPARATION OF be fused with a benzene ring, w : . NO-DISUBSTITUTED URETHANES USEFUL FOR R2 represents an optionally substituted alkyl radical THE PREPARATION OF SOCYANATES containing from 1 to 20 carbon atoms, an option 5 ally substituted cycloalkyl radical containing from: BACKGROUND OF THE INVENTION 3 to 16 carbon atoms and an optionally substituted: This invention relates to an improved process for the aralkyl radical containing from 7 to 14 carbon preparation of urethanes in which urea or polyurets, atoms, and . , , , amines and alcohols are reacted in the presence of N n represents an integer of from 1 to 3. unsubstituted urethanes and/or N-mono- or N,N'-disub 10 When n represents 2 or 3, at least 2 carbon atoms should stituted ureas or polyureas. ." be arranged between the 2 urethane groups attached to It is known that urethanies may be formed by reacting the radical R1. - organic isocyanates with alcohols. This reaction is re Substituents for the aliphatic or cycloaliphatic radi versible, i.e., the urethanes so formed may be thermally calls R1 and R2 include C6-C10 aroxy, C1-C6 alkoxy, split into the isocyanate and the alcohol on which they 15 C1-C6 alkoxy-C-C4 alkoxy, C1-C6 acyl, C1-C6 alkyl are based (see, for example, U.S. Pat. No. 2,409,712). mercapto, C6-C10 aryl mercapto, C1-C12 alkyl car Urethanes which may be thermally split into isocya bonyl, bis-(C1-C8 alkyl)-amino, C-C6 acyl amino, ni nates are, therefore, potential starting materials for the tro, cyano and thiocyano radicals. preparation of isocyanates. In addition to these substituents, suitable substituents : Isocyanates have been almost universally prepared 20 for the aromatic or araliphatic radicals R1 and R2 in by reacting primary amines with phosgene. However, clude C1-C12 alkyl, C1-C12 alkylsulfonic acid ester and the preparation of urethanes without phosgene and the sulfonamide radicals. subsequent thermal splitting of these urethanes would The preferred products of the process of the present be an interesting alternative. One method for preparing invention are those corresponding to the above-given urethanes without the use of phosgene is to react urea 25 general formula wherein : with amines and alcohol. Such a method is described in R1 represents an aliphatic hydrocarbon radical con U.S. Pat. Nos. 2,409,712 and 2,806,051. However, these taining from 3 to 18 carbon atoms, a cycloaliphatic known methods produce urethanes which contain nu hydrocarbon radical containing from 6 to 15 car merous secondary products in inadequate yields. bon atoms or an optionally methyl-, methoxy- or 30 chlorine-substituted C6-C15 hydrocarbon radical SUMMARY OF THE INVENTION optionally containing methylene bridges, - It is an object of the present invention to provide an R2 represents a C1-C4 alkoxy or C1-C4 alkoxy-C2-C improved process for preparing urethanes by reacting alkoxy substituted or unsubstituted aliphatic hydro urea with alcohols and amines in such a way that the carbon radical containing from 1 to 18, more part. N, O-disubstituted urethanes are obtained in amounts 35 ticularly from 1 to 4, carbon atoms of the type greater than those achieved with known methods. obtained by removing the hydroxyl group from a It has now surprisingly been found that this, object monohydric, unsubstituted primary or secondary may be achieved by using materials containing carbonyl aliphatic alcohol, or a cyclohexyl or 2-phenyl ethyl groups in addition to the urea and/or polyurets, amines radical, and . and alcohols known in the art. n represents 1 or 2. The present invention relates to a process for the preparation of N.O-disubstituted urethanes by reacting: DETAILED DESCRIPTION OF THE (a). urea or polyurets with PREFERRED EMBODIMENTS (b) primary. amines, and . The present invention is a process for producing (c) alcohols attemperatures of from 120° to 350° C., 45 urethanes in which urea and/or polyurets, primary characterized in that " . amines, alcohols, N-unsubstituted urethanes and/or (d) N-unsubstituted urethanes and/or N-mono- or N,N'-disubstituted urethanes are reacted at (e) N-mono- or N,N'-disubstituted ureas or polyureas a temperature of 120 to 350° C. are used as further reactants. Starting materials for the process according to the The process according to the present invention is 50 present invention include urea or polyurets, particularly particularly suitable for the preparation of urethanes biuret, triuret or tetrauret, corresponding to the follow corresponding to the following general formula: ing general formula: 55 wherein m represents an integer of from 1 to 4, or mix tures of these compounds. ---- Primary amines which may be used as a starting mate wherein . rial in the present invention correspond to the general R1 represents an optionally substituted aliphatic hy formula: drocarbon radical containing from 1 to 18 carbon atoms, an optionally substituted cycloaliphatic hy drocarbon radical containing from 3 to 18 carbon atoms, an optionally substituted aromatic hydro wherein R1 and n are as defined above. carbon radical containing from 6 to 15 carbon 65. Examples of suitable amines include: methylamine; ... atoms, an optionally substituted araliphatic hydro ethylamine; propylamine; isopropylamine; butylamine; carbon radical containing from 7 to 14 carbon i-butylamine; t-butylamine; hexylamine; dodecylamine; atoms or an optionally substituted 5- or 6-mem 2-ethyl-hexylamine; tetradecylamine; hexadecylamine; 4,430,505. 3 4. octadecylamine; allylamine; 1,4-diaminobutane; 1,6- octanol; i-octanol; nonanol; i-nonanol; decanol; i diaminohexane; 2,5-dimethyl-2,5-hexane diamine; tri decanol; dodecanol; 2-ethyl hexanol; (3-chloroethanol; methylhexamethylene diamine; 2-methoxy-ethylamine; 2-ethylbutanol; hexadecanol; octadecanol; fatty alcohol 3ethoxy-propylamine; 3-butoxy-propylamine; 1,4- mixtures; 2-methoxy 'ethanol; 2-ethoxy ethanol; 2 butane diol-bis-(3-aminopropyl ether); 3-amino propoxy ethanol; 2-butoxy ethanol; 2-(2-methoxy propanoic acid-2-methyl propyl ester; 6-aminohexani ethoxy)-ethanol; 2-(2-ethoxy ethoxy)-ethanol; 2-(2- trile; lysine ester; 1,1-amino-undecanoic acid ester; cy butoxy ethoxy)-ethanol; cyclopentanol; cyclohexanol; clohexylamine; trimethyl cyclohexylamine; 2-riorbor methyl cyclohexanol (and mixtures); cyclohexame nyl-methylamine; aniline; o-, m-, p-chloroaniline; 2,3-, thanol; 3,3,5-trimethyl cyclohexanol; 4-t-butylcy 2,4-, 2,5-, 2,6-dichloroaniline; 3,4-dichloroaniline;p-, 10 o-nitroaniline; m-, o-, p-tolylamine; 3-trifluorome clohexanol; 2-hydroxy decalin; borneol; i-borneol; 1-(2- thylaniline; 3-chloro-4-methylaniline; benzylamine; hydroxyethoxy)-4-nitrobenzene; benzyl alcohol; 2-phe phenyl-cyclohexylamine; naphthylamine; 1,4- nyl, ethanol; 2-(methoxy phenoxy)-ethanol (and mix diaminocyclohexane; 2,4-, 2,6-diamino-1-methyl cyclo tures); 1-phenyl ethanol; 3-phenyl-1-propanol and 4 hexane; 5-amino-1-aminomethyl-1,3,3-trimethyl cyclo methoxybenzyl alcohol. hexane; 4,4'-diaminodicyclohexylmethane; 4,4'- 15 Particularly preferred alcohols include: methanol, diamino-3,3'-dimethyldicyclohexylmethane; 1,3- ethanol, n-propanol, i-propanol, n-butanol, i-butanol, . diaminobenzene; 1,4-diaminobenzene; 2-chloro-1,4- cyclohexanol, n-hexanol, 2-ethylhexanol 3-phenyl eth diaminobenzene; 2,4-diaminotoluene; 2,6-diaminotol anol, glycol monomethyl ether, glycol monobutyl ether uene (and mixtures with 2,4-); 2-(N-ethylamino)-4- or diglycol monomethyl ether. aminotoluene; 1,3-diamino-2-methylbenzene; 1,3-bis An essential characteristic of the present invention is aminomethylbenzene; 1,3-bis-aminoethyl-4,6-dimethyl the use of compounds containing carbonyl groups. Suit benzene; 1,3-diamino-2,6-(4,6)-diethyl-4-methylben able carbonyl compounds include: N-unsubstituted ure Zene; 1,3-diamino-2,4,6-triisopropylbenzene; 1,5- thanes and/or N-mono- or N,N'-disubstituted ureas or diaminonaphthalene; 2,7-diaminonaphthalene; benzi polyureas.
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