Патент USA US2409677код для вставки
Patented Oct. 22, 1946 2,409,675 UNITED STATES PATENT OFFICE ” PREPARATION1 OF 2,409,675 VPOLYAIWINOACETALS ‘ . ‘I v ‘ William Franklin Gresham, Wilmington, Del., as signor to E. I. du Pont de Nemours ‘8r Company, Wilmington, Del., a corporation of'Delaware No Drawing.‘ Original application February 14,. 1942, Serial No. 430,945. Divided and this ap plication’Decemb'er 26, 1944, Serial No. 569,915 . 5‘Claims. p (01. 260-584) 2 ‘1 Genen'cally the reaction may be illustrated as This invention relates to polyaminoacetals, to processes for their preparation, and especially to their preparation from ‘acetals and cyanohy proceeding in accord with the equations, drins and more particularly from formals and cyanohydrins. The applicationis a division of in which R is an alkyl or substituted ‘alkyl group, R’ is hydrogen, an alkyl or substituted‘ alkyl group, and Y is a single bond or. analkyl group; The over-all process of the invention includes the alcohol being removed by distillation as three steps. ‘ In the ?rst step, cyanoacetals are prepared by the reaction of an acetal of an alde 10 formed. More speci?cally the reaction may be illustrated by the preparation of (methoxymeth hyde and/or a ketone with a ‘cyanohydrin of an my copending application S‘. N. 430,945 ?led Feb ruary 14-, 1942. ‘ l ‘ oxy) acetonitrile in accord'with‘the equation: aldehyde‘and/or a ketone in ‘the presence of a suitable acidic type catalyst.- In the second step, the cyanoacetal of the ?rst step is hydrogenated to give the corresponding aminoacetal and. in 15 While the reaction proceeds primarily‘ between the third step of the process the, aminoacetal is one mole of the ‘acetal and one mole of the cyano converted to a salt and the resulting salttreated -‘hydrin, nevertheless, a reaction likewisetakes to liberate the polyaminoacetal by‘ disproportion ation._ place between one mole of the acetal and two ,l. An object of. the invention is to provide new v20 moles of the cyanohydrin to give two moles of al cohol and one mole of a dinitrile. The invention provides a method for the prepa chemical compounds, viz.-di(aminoalkyl) acetals. Another object of the invention is to provide a ration of cyanoacetals by the interaction of the cyanohydrins and their equivalents listed in the step process ‘for the preparation'of di(aminoal .125 following paragraph. with the acetals and their equivalents listed herewith. As examples of suit kyl), acetals and ketals together with reaction ‘process for the preparation of .di(aminoalkyl) acetals.v Still another object is to provide a three conditions‘therefor. Other objects and advan tages of the invention will hereinafter appear. In the ?rst step of the process acetals of alde hydes‘or ketones are reacted with Thiscyanohydrins reaction is of aldehydes and ketones. eifected by mixing the acetal and cyanohydrin able acetals, may be designated the symmetrical acetals which may be prepared by reacting form aldehyde or a higher aldehyde such as acetalde propionaldehyde, normal and isobutyralde 30 hyde, hyde with an alcohol, such, for example, as meth anol, ethanol, normal and isopropanol, normal in the presence, of a suitable acidic type catalyst and isobutanol and the higher alcohols ‘such as mately 300° C. ‘ In many instances, however, no heating is necessary as the reaction proceeds at room temperatures down to in the neighbor methyl propyl formal, ethyl‘propyl formal,‘ methyl ' hood of 0° C. Pressures‘ may be employedif desired ranging from'atmospheric to 100: atmos pheres or more, although for normal operation ketals,‘ may likewise be used and as examples of these compounds which may be employed are pressures above atmospheric are not necessary. , . those prepared by the interaction of ketones such In order to force the reaction to completiomit as acetone, methyl ethyl ketone, diethylketone, and ‘the higher symmetrical and unsymmetrical ketoneswith the alcohols designated‘ above,‘ the cyclic formals and- their poly'mers‘likewise may nonyl, decyl, cyclohexyl and like straight and such, for example, as sulfuric acid, hydrochloric branched chained alcohols.‘ The above acetals acid, phosphoric acid, boron ?uoride (or its addi .35 are primarily of the symmetrical‘ type, unsym tion products), paratoluene sulfonic acid or the metrical acetals, however, ‘may. likewise be em like and heating the resulting mixture to a tem ployed, such,_,fcr example, as methyl ethyl formal, perature from room ‘ temperature ,to approxl- ' is preferable to remove from the reaction zone the alcohol ‘producedJ v'I‘his‘may be done con tinuously or intermittently as desired. Subse quent to the reaction the catalyst is preferably neutralized with a base either organic or inor ganic such as, for example, sodium hydroxide, sodium carbonate, sodium methoxide, pyridine, or the like and the products distilled for the recov-, ery of thecyanonitrile produced. (methoxymethoxyl ethanol, methyl ethyl acetal, propyl acetal, and the like. lAcetals of the'type made from ketones and: alcohols, sometimes called belused such,-for example, as 1,3-dioxolane, poly-. so meric 1,3-dioxolane, glycol formals, 1,3-dioxane andltheir substitution products. , ‘ . ' The above designated. acetals may be reacted with such cyanohydrins and their equivalents, as, for. example, those prepared ‘by the interac 2,409,675 3 4 tion of hydrocyanic acid with the aldehydes gen erally, such as formaldehyde, acetaldehyde, pro ethanol stopped distilling from the mixture. After neutralizing the mixture, as described above, pionaldehyde, normal and isobutyraldehyde and the higher aldehydes. Ketone cyanohydrins are fractionation was continued. likewise suitable and as examples of these com in 67% yield, boiled at 70° at 3 mm. pounds-may be designated those‘pre'pared by the interaction of hydrocyanic acid “with acetone, Example 7.-—'A mixture of diisobutyl formal (1 'mol), acetaldehyde cyanohydrin (1 mol), and methyl ethyl ketone, diethyl ketone, cyclohexan sulfuric acid (2 cc.) was heated on an oil bath rI‘he (methoxy ethoxymethoxy) acetonitrile fraction, obtained one, and the higher symmetrical and unsym and the isobutanol formed in the reaction was metrical ketones. Hydroxy acid nitriles ‘which 10 ‘tilled from the mixture at reduced pressure (55 may be called glycol cyanohydrins may also be mm.) during the reaction. After a 6 hour reac tion period the product, alpha (isobutoxymeth used such, for example, as ethylenefg‘lycol'cyano hydrin, HOCHzCHzCN, propylene ‘glycol cyano "oxy) propionitrile, was washed with water and distilled at 3 mm. hydrin, HOCHzCI-IzCI-IzCN, and’so forth. The more detailed practice of this step ‘of the 15 Example 8.——Acetaldehyde cyanohydrin was invention is illustrated by the following exam ‘heated to a temperature between 60 and 90° C. ples in which parts are by weight unless other with excess'methylal and sulfuric acid catalyst in a pressure still operating under 30# gauge wise stated. Example 1.—A mixture consisting of 228 parts pressure. Methylal and methanol were distilled of formaldehyde cyanohydrin, 1648 parts of 20 from the reaction mixture during the reaction ‘methylal (as a methanol‘azeotrope containing 8% at 77° C. atthis pressure. The pressure was re methanol and 92% methylal) and 10 parts of leased and the mixture neutralized as described sulfuric acid was boiled ?ve hours, Catalyst was 'above'and after distillation a conversion of 45% to 'methoxymethoXy-propionitrile was realized. The above valuable nitriles can be readily con tilled. 110 parts of the product (methoxy-meth verted to amines by hydrogenation. This may be effected preferably in the liquid phase employing oxy) acetonitrile CHsOCHzOCHaCN, a colorless, 'm'obile liquid with a B. P.‘ 66° C./23 mm. was ob a ‘suitable active hydrogenation catalyst such, for ‘tained. example, as a nickel, cobalt, fused copper-cobalt, Example 2.——Two moles of isobutyraldehyde 30 "copper chromite catalyst or the like. The hy cyanohydrin was reacted with 3 moles of isobutyl drogenation can be conducted in the liquid or vapor phase at temperatures ranging'between 25 ‘formal in the presence ‘of 0.1‘mole of sulfuric acid. and 200° C. and at pressures between 1 and 1000 The resulting mixturewas’heated'to ‘a tempera atmospheres although it is preferred to conduct ture in'the'neighborho‘od‘of 100° C. for ?ve hours, the hydrogenation \of‘these nitriles at tempera subsequent to which sodium methoxide was added tures'between 75 and 150° C. and under pressures ‘to neutralize the catalyst‘an'd until the solution neutralized, as indicated by phenolphthalein, by the addition of NaOHCa and the product was dis was neutral as indicated by phenolphthalein. between v200 and 700 atmospheres. An 81.4% ‘conversion of valpha (isobutoxymeth 'It 'has ‘likewise been found that polyamine formation during hydrogenation is inhibited, oxy) isovaleronitrile Y Yo oHl'o oil-19 '(CHMCHCHON was ‘obtained. It ‘is a white, Water-immiscible oil, boiling point 67° C. at 2 mm. Example 3.—A reaction mixture ‘consisting of 114 parts of formaldehyde cyanohydrin, 320 parts of diisobutyl'formaland 2 parts of sulfuric acid was fractionated until no more isobutanol dis ' 40 yieldsare increased, and the reaction goes more smoothly if ‘there be present durin'g'the reaction from v1 to 20 moles of ammonia per ‘mole of the nitrile. If ‘desired, the nitrile'to be hydrogenated ‘may-be dissolved in aqueous ammonia or the ‘nitrile may be'dis'solved in a ‘suitable solvent such, for example, as methanol, 'di(isopropyl) ether, vdioxarie, or 1,3-dioxolane, which is not decom p'o's'ed or hydrogenated during the reaction or de tilled 'from'the mixture. ‘After neutralizing’the composed by‘the ammonia added to the solution. mixture with sodium hydroxide, using litmus as 50 vThis step 'of the process may be illustrated by 'the'following'equation: th‘ejindicator, fractionation was continued. The (isobutoxymethoxy) 'acetonitrile fraction, ob .tained in 83.3% yield, boiled'at 50° at 3 mm. Example 4.——A reaction mixture'consisting ‘of 114‘pa'rts of formaldehyde cyanohydrin, 320 parts 55 which illustrates the hydrogenation of an (al koxymethoxy) acetonitrile to an (alkoxymeth oxy) ethyl amine. In accord with this process the other nitriles described and illustrated'under tilled from the mixture. After neutralizing the step 1 ‘of the process may be ‘similarly converted mixture with sodium hydroxide, using litmus as the indicator, ‘fractionation was continued. The 60 ‘to the'corresponding amine, In order to illustrate this step of the process, (cyanomethoxymethoxy) acetonitrile fraction sever'al'speci?c embodiments of the invention are 'ob'ta'ined‘in 10% yield, boiled at'1l0° at 2 mm. described herewith by way of example. _ Example 5.-—A reaction "mixture consisting of Example 9.——~A reaction mixture consisting of 228 parts'of formaldehyde cyanohydrin, 541 parts 78.3 parts of (isobutoxymethoxy) 'acetonitrile, of diethyl formal'and 2 ‘parts‘of sulfuric acid was l'00sparts of ammonia, and 20 parts of an active fractionated until ‘the binary of diethyl formal nickel hydrogenation catalyst supported on and ethanol stopped distilling from the mixture. kieselguhr was subjected to the action of hydro After ‘neutralizing the mixture, as described gen at 100°C. and 700 atmospheres pressure for above, fractionation ‘was continued. The ethoxy methoxy a'cetonitrile fraction, obtained in 57.0% 70 '1i5'hours. After removing catalyst the product was distilled. Isobutyl aminoethyl formal, yield,'boiled at 45° at 1 mm. of diisobutyl formal ‘and 2 ‘parts of sulfuric acid was fractionated until no more ‘isobutanol dis Example 6.-—A reaction mixture consisting ‘of 142 parts of formaldehyde cyanohydrin, 277'parts _ (CH3)2CHCH2OCH2OCH2CH2NH2 'of‘di(methoxyethyl) formal and 2 parts vof sul ‘(135R some/4 mm.) was ‘obtained in 9115 %_- yield. furic acid was ‘fractionated until “methox'y 75 Example 10.-A reaction mixture‘con-sistmgrbr 2,409,675 5 6 50 parts of (isobutoxymethoxy) acetonitrile, 100 parts of diisopropyl ether, 20 parts of an active methanol, ethanol, or 1,4-dioxane, with ammonia to precipitate the ammonium salt with liberation nickel‘ hydrogenation catalyst (prepared as in Example 9) andv 50 parts of ammonia was sub of the. amine acetal. In' a similar manner the other products of steps 1 and 2 as well as other aminoacetals may be converted to diamines. In order to illustrate .the third step of the process several specific embodiments of the in - jected to the action of hydrogen at 100° C. and . .700 atmospheres pressure for one hour. After removing the catalyst the product was distilled. Isobutyl aminoethyl formal was obtained in ‘79.9% yield. ‘ ‘ vention are given. The invention, however, is not to be restricted by these or the other exam Erample 11.-—-One mole of (methoxymethoxy) 10 ples given. Example 12.—To 73.5 parts of isobutyl amino acetonitrile dissolved in. 12' moles of ammonium hydroxide containing 10% nickel catalyst was ethyl formal, C4H9OCH2OCH2CH2NH2, was added subjected to the action of hydrogen at 100° C. 20 parts of dry HCl gas with cooling by means of and ‘700 atmospheres pressure until the reaction an external ice bath. After the addition the mix was complete.‘ The catalyst was removed and 15 ture consisted of a white solid suspended in a the product distilled. Methyl aminoethyl for mobile liquid. Di-isobutyl formal was removed mal, CHsOCI-IzOCHzC‘HzNI-Iz was obtained in a from the reaction mixture at 2 mm. pressure. To practically quantitative yield as a colorless, mo the solid remaining ‘110 parts of 29.6% NaOCHs bile liquid (B. P. 56-57" C‘./30 mm). in CHsOH was added and NaCl then ?ltered off. Similarly, methoxyethyl aminoethyl formal 20 The product was distilled and di(aminoethyl) ‘ can be made from (methoxyethoxymethoxy) ace tonitrile; isobutyl 1-amino-3-methyl-2-butyl for mal from (isobutoxymethoxy) isovaleronitrile; and methyl l-amino-2-methyl-ethyl formal from (methoxymethoxy) propionitrile. It has likewise been found that the amines, formal (NH2CH2CH2O)2CH2, B.IP. 70° C./2 mm. obtained in a yield of 90% or better. Example 13.—58.8 parts of isobutyl aminoethyl formal was placed in a suitable container, cooled, agitated and 20 parts of anhydrous hydrochloric prepared in accord with step 2 by hydrogenation acid was introduced. As a result of this reaction diisobutyl i. formal was produced and withdrawn in the presence of ammonia of the nitriles pre pared in accord with the process of step 1, can be by distillation under reduced pressure leaving the or inorganic acid, the addition preferably being repeated using 212 parts of ethyl aminoethyl formal, C2H5OCH2OCH2CH2NH2, and 65 parts of hydrochloric acid. Di(aminoethyl) formal was salt of the diamine as a white solid. The salt converted into salts and by disproportionation 30 was converted to the free base by neutralization these salts converted to polyarninoacetals. to phenolphthalein by the addition of sodium The salts may be prepared, for example, by methoxide. The precipitated sodium chloride adding to the aminoacetals an organic or inor was ?ltered off and the ?ltrate fractionally. dis ganic acid such, for example, as hydrochloric tilled to give di(aminoethyl) formal, obtained in acid, sulfuric acid, phosphoric acid, acetic acid, 35 a 90% yield. glycolic acid, oxalic acid or other suitable organic . Example 14.-—The process of Example 13 was carried out at a temperature between 0 and 100° C. The salt thus prepared is then reacted with a suitable base such as the alkali metal or alka obtained in a yield of substantially 90%. Example'15.-20 parts of di(aminoethyl) for mal hydrochloride dissolved in 60 parts of iso ?ltering off the precipitated salt, if present, the butanol is saturated with anhydrous ammonia aminoacetal is distilled from the ?ltrate. and the ammonium chloride formed rapidly pre This step of the process may be illustrated by 45 cipitates. The solution was ?ltered and the 1di line earth metal hydroxide, carbonate, or alkox ide or an organic base such as pyridine, and after the following equations; (ethylamino) formal separated by distillation, Similarly di(aminoethyl)formal can be ob tained from methyl aminoethyl formal, CHaOCHzOCHzCHzNHQ methoxyethyl aminoethyl formal, in which R. is an alkyl or substituted alkyl group, R’ is hydrogen, an alkyl or substituted alkyl CHsOCI-IzCHzOCHzOCHzCI-IzNI-Iz and from like products. Those skilled in the art group, Yis a single bond or an alkyl group and 55 will appreciate that other aminoalkyl formals X is the anion of a mineral acid. and acetals can be obtained from corresponding More speci?cally this step of the process may monoamine alkyl formals and acetals to give be illustrated by the equations: products having the formula: 7. ROCHzOCHzCHzNI-Iz-I-HClé ROCHzOCHzCHzNI-IzHCl 60 in which R’ is hydrogen, an alkyl or substituted alkyl group. The products of the invention have a wide va riety of uses. The diamines may be reacted with (alkoxy-methoxy) ethyl amine to its hydrochlo 65 dibasic acids, such as adipic acid, to form salts from which linear polymers of great utility may ride and Equation 8 illustrates the disproportion ation of the hydrochloride to a poly salt. The be produced and in addition to being useful in the disproportionation results when excess acid over preparation of the diamines the intermediates are that used to make the salt is added. Subsequent useful as plasticizers, softeners, thickeners, non treatment of the polyhydrochloride by an equiv polar detergents, softeners, and plasticizers for alent quantity of a base, ?ltering to remove the regenerated cellulose, cellulose ethers, esters, and chloride salt and fractionally distilling the fil the like. trate will give the corresponding di(ethylamine) I claim: 1. A process for the preparation of a di(amino formal, CH2(OCH2CH2NH2) 2. If desired, the salts may be treated in a suitable solvent, such as alkyl) acetal which comprises heating an acetal Equation "1 illustrates the conversion of an '7 with aldehyde cyanohydrin whereby an unsym fine‘t'riéal cyanoalkyl acetal is obtained, heating the resulting cyanoalkyl acetal with hydrogen in thelpresence of ammonia and a hydrogenation catalyst to form an unsymmetrical aminoalkyl with formaldehyde cyanohydrin, producing “methyl aminoethyl formal by subjecting (meth ‘o'xymethoxyl acetonitrile to a reaction with hy drogen at a temperature between 25° and 200° C. in the presence of ammonia and a hydrogenation ‘acetal, separating the unsymmetrical aminoalkyl catalyst, separating the methyl aminoethyl for acetal from the hydrogenated reaction mixture, subjecting the separated unsymmetrical amino mal from the hydrogenation mixture, subjecting the methyl aminoethyl formal to a reaction with an excess of an inorganic acid, neutralizing the inorganic acid, neutralizing the salt obtained with 10 resulting salt with a base and after ?ltering, and recovering di(aminoethyl) formal from the reac 'a base, and ‘subsequently removing from the re alkyl acetal to a reaction with an excess of an sulting mixture after ?ltration the di(amino tion mixture by distillation. 4. In a process for the preparation of di(ami n'oethyl) formal the steps which comprise sub 'alk'yl) formal which comprises heating a formal T15 jecting isobutyl aminoethyl formal to a reaction -2. A process for the preparation of a di(amino withforr'naldehyde cyanohydrin whereby an un symmetrical cyanoalkyl formal is obtained, heat ing the resulting cyanoalkyl formal with hydro with an inorganic acid and thereby forming a mono salt of the formal, subjecting said mono salt to a reaction With an additional quantity of a mineral acid to form a di(aminoethyl) formal g‘enin the presence of ammonia and. a hydrogena ‘tion‘c'atalyst to form an unsymmetrical amino 20 salt, neutralizing the’ latter salt with a base and alkyl formal, with hydrogen in the presence of recovering the di(aminoethyl) formal from the ammonia and a hydrogenation catalyst to form reaction mixture by distillation. an unsymmetrical aminoalkyl formal, separating 5. In a process for the preparation of di(ami the unsymmetrical aminoalkyl acetal from the noethyl) formal the steps which comprise adding hydrogenated reaction mixture, subjecting the 25 ‘approximately 20 parts of dry hydrochloric acid separated unsymmetrical aminoalkyl formal to a gas with cooling to approximately 731/2 parts of reaction with an excess of an inorganic acid, neu isobutyl aminoethyl formal, separating the pre tr'a'lizing the salt obtained with a base, and sub cipitated salt by ?ltration, adding approximately sequently'rem'oving from ‘the resulting mixture 110 parts of a 29.6% sodium methoxide solution after ?ltration the di(aminoalkyl) formal. in methanol, ?ltering o? the sodium chloride and 13. A process for the preparation of di(amino recovering the di(aminoethyl) formal. ethyl) vformal which comprises producing meth oxymethoxy) 'ac‘etonitrile by heating methylal WILLIAM FRANKLIN GRESHAM.