amino“. 5, 1943' l ‘ 2,331,276

.. 'UNI'TED‘STATES PATENT OFFICE

CYANATES AND PROCESS OF PREPARING THE‘ SAME ‘ Jose: rm, Pitman, N. J. , assignor to E. I. in Pont de .Nemours & Company, ' Del, a corporation of Delaware 7 on, No Drawing. Application October 30, 1940, Serial No. 363,524 ' 12 Claims. (CI. 260-4025) 'This invention relates to novel organic com other alkyl groups, or by alkyloxy, alkylamino, pounds and to a process for preparing the same. or acyl imino groups, having an alkyl chain of . More particularly this invention deals with-novel from 9 to 36 carbon atoms, while the and isothiocyanates obtainable by radical -—SCN, may be replaced by the isothio condensing a salt of with halo cyanate radical, -—NCS; geno-methylam'ides having long-chain alkyl radi These compounds are prepared, according to cals in their structure. this invention, by reacting with a salt of mm It is anobiect of this invention to prepare novel 'cyanic acid, for instance an alkali-metal thic organic compounds which are useful in the art cyanate or a heavy metal thiocyanate, upon an ‘ of treating textile ?ber, especially for the pur 10 amido compound of the general formula pose of endowing the same with water-repellency or with softness of feel. Further important ob R——Y—1?'—CHz—-X- ' jects of this invention will appear as the descrip I , - R’ . tion proceeds. wherein R, Y and B.’ have the same significance The novel compounds of this invention are 15 vas above, while X stands for halogen,‘ preferably characterized by a structure corresponding to the ‘chlorine or bromine. , following general formula At first‘ a thiocyanate is formed, which how ever in most cases rearranges gradually to give the isothiocyanate. Taking stearamido-methyl I 20 chloride and as conven - wherein R is an aliphatic or alicyclic radical (in ient individuals for the purpose of illustration, other words, a non-aromatic radical) containing. the reactions may be expressedby the following at least 7 carbon atoms and, being free from equations: . water-solubilizing groups. Y is a link selected .from the group consisting of C0,, 0,-CO, 25 NH-CO, CO-NHCO and O-GO-NHCO; R’ stands for hydrogen, a lower alkyl-group, or a lower alkylene group which is attached to the nitrogen atom of another radical of the form At room temperature, the rearrangement is 30 very slow and may take several weeks for com ‘ R-Y-IlI-CHr-Q plete isomerization. But by heating to conven (R, Y and Q having the same signi?cance as ient temperatures, say up to 100° C., the process above) ; and ?nally, Q stands fora radical of the may be completed within a few hours. group consisting of the thiocyanate radical 'The ease with which the chloromethyl com --S—CN and the isothiocyanate radical --N—CS. ,- pounds react with the salts of thiocyanic acid As typical illustrations of compounds falling 7 depends greatly upon the content of moisture of within the above general class may be mentioned , the‘ reaction mass. If the metal thiocyanate con ‘ at this point: tains a small amount of moisture, that is from 2 Stearamido-methyl-thiocyanate: ‘ to 5% by weight, the reaction proceeds readily 40 at room temperature and is ?nished in several Ci7I'I35—CO—-NH—CH2——SCN , hours. If the reaction medium is perfectly dry no noticeable reaction takesplace at ‘room tem N-methyl-stearamido-methyl-thiocyanate: perature, but a higher temperature such as 60 CnHas-C0—N—CH:—SCN . to 100° C. is necessary to bring the reaction about. Ha ' ‘ 45 The reaction is usually carried out in an inert and medium such as benzene, carbon tetrachloride, cyclohexane, trichloroethylene or ethyl acetate, ' Methylene-bis(stearamido-methyl-thiocyanate) : ' but it may also be carried out in the absence of a solvent by simply heating the chloromethyl amide '50 with a salt of thiocyanic acid and then separating ' the inorganic salts from the reaction mass by a suitable solvent or by ?ltration at a temperature My invention, however, is not limited to these above the melting point of the reaction product. compounds, since it embraces compounds wherein This ‘reaction may also be carried out under the group CnHas above is replaced by ‘various at vacuum if the reaction products are, not volatile. 2 2,331,276 ‘ The amount ' of- the salt of thiocyanic acid and similar compounds derived from other higher necessary to carry the reaction to completion may fatty acids or alcohols, whether saturated or un be one mol equivalent per mol of the chloro saturated, straight-chain or alicyclic, (for in methyl derivative or in excess thereof, as there stance naphthenicand 'hydroabietic), and which ' _ is no difficulty involved in separating the organic are generally. derived from the constituents of thiocyanate from the inorganic salts. A large natural oils, fats and waxes. ~ ' excess of inorganic thiocyanate may be used. The chloromethylene derivatives of these‘ In the reaction between the organic methylene amides are usually low melting solids which are chloride and the inorganic thiocyanate, any very soluble in solvents like benzene or carbon residual acidity left in the product or occluded 10 tetrachloride. They may be prepared as de therein may be eliminated by carrying out the re scribed in the above mentioned patents by react action in the presence of a small amount of a ing the amide with gaseous hydrogen chloride and basic reagent like sodium'carbonate, barium car paraformaldehyde, or by using an aqueous form~ bonate, magnesium oxide», or pyridine. The addi aldehyde solution and hydrogen chloride gas, or tion of these products tends also to decrease the even by using aqueous formaldehyde and aqueous formation of by-products. "When the reaction is hydrochloric acid. In this latter case it is, how complete, it is desirable to~ neutralize any free ever, advisable to use some calcium chloride or acids which may remain in'the‘ reaction product another water removing agent together with the by stirring the product with a slightly moist basic formaldehyde and hydrochloric acid. The chloro material like potassium carbonate, calcium oxide 20 methylene compounds may also. be prepared by or magnesium oxide. In this way a product can the action of hydrogen chloride on the correspond-v be obtained which is neutral to Congo red paper. ing methylol amides. ‘ The last traces of moisture may be removed by After the preparation of the chloromethyl com ' treatment with some 'drying agents like CaClz, pound, the excess of hydrogen chloride is re moved either by evaporating the solvent in vacuo sodium , or alumina. The initial methylene halide compounds em or byblowing an inert gas like'COz or N2 through ployed in my invention maybe selected from the solution until all or most of the HCl is re among any of the compounds described and moved. . In view of the slow process of isomerization, claimed in U. S. Patent No. 2,131,362, or in the products of this invention are generally prob British Patents Nos. 492,699, 494,761 and 501,480, 30 ‘ and may be prepared by the methods therein set ably mixtures of thiocyanates and isothio forth. Generally speaking, these compounds are cyanates, whose exact composition varies with prepared by reacting with formaldehyde and hy _ the age of the product, and whose properties are drogen chloride on an amide compound of the a composite ‘result of the properties of the indi general formula R—Y—-NH-—R', wherein R, Y vidual components and their relative proportions and R’ have the same signi?cance as above, it be at any given time. ing noted that Y always contains a CO group next ' The pure thiocyanates, which may be approxi to the NH, thus placing the compound in the mated by the products of this invention as fresh classification of amides. As typical illustrations ly prepared, are generally oils or low-melting of such amide initial material, without however 40 waxes, soluble in benzene and other common or any intent to limit this invention, may be men— ganic solvents. They react readily with tertiary bases to give crystallizable, water-soluble com tioned: pounds, presumably quaternary ammonium com Stearamide: pounds, thus: ‘ ' C1'zI-h5—CONH2 45 \Octad'ecyl-carbamate: C1sI‘Is'r-O-'—CONI-I2 Octade cyl-urea : 50 ‘ C1sH31-—NH-CO—NH2

Stearyl-urea: - CrvI-Isa-CONH-CO-NH: Octadecyi-allophanate: . 55 The quaternary compounds are stable both C1aH3v—-O-—CONH—-CONH in substance and in aqueous solution, and no Methyl-stearamide: ' longer isomerize into isothiocyanates. They are CrzI-Ias-C ONH-CHa also solublein organic solvents, and concentra Distearamido-methane: tions' thereof up to 50% by weight may be readily 60 CnHaa-C ONH prepared. When cotton fabric is treated with an aqueous solution (0.2 to 2%) of these quater H: nary compounds and then ‘dried and baked in the _ ‘ CnHas-C 0111K absence of moisture at a temperature between 100 Montanic acid amide: and 170° 0., it acquires a soft feel and a high de 65 gree of water-repellency, both of which proper ties are permanent to laundering and dry-clean 2-hexadecyl-eicosanoic acid amide: ing. Smaller concentrations, say 0.01 to 0.2% are CmHar-CIEL-C ONH: su?icient to impart softness to fabric under the

. mHza same treatment. - 70 Similar effects upon fabric may be obtained by Tiidecamethylene-diamide: - similar treatments using the thiocyanates them - 0 ONE: selves from organic solution, for instance ben (0112)“ zene, trichlorethylene or carbon tetrachloride. 0 ONE: 75 The pure isothiocyanates, which may be ap 2,331,276 , 3 proximated by the products of this invention after When applied to cotton and rayon ta?'eta from standing for‘ several months, are likewise oils or a 1%.solution in benzene and then subjected to , low melting waxes. They do not, however, react a baking step, the fabrics became strongly water with tertiary bases to give water-soluble com repellent, which property was fast to washing. ‘ _ pounds, and this test may be used to estimate at any given time the percentage conversion or ’ Example 3 ' s - isomerization of a given sample. Like the thlo _220 parts of methylene distearamide was con cyanates, the iso-compounds are soluble in ben verted into'the corresponding di-chloromethyl zene, trichlorethylene, carbon tetrachloride, and compound by suspending the amide in 800 parts similar common‘ organic solvents, and when ap 10 of benzene and then adding, in the course of plied from such solutions to textile ?ber, they one and one-half hours, 36 parts of parai'ormal produce effects similar to those above described. _ dehyde, while passing in a. stream of gaseous hy Without limiting my invention to any particu drogen chloride,~as described in Example 1. The lar procedure, the following examplesare given ' residue which was obtained upon evaporation ‘to illustrate my'preferred mode of operation. 15 was diluted with 50 parts of benzene and added Parts' mentioned are by weight. , to ‘a suspension of 250 parts of lead thiocyanate in 250 parts of boiling benzene. The lead salt ‘ i ' Example 1' had been previously thoroughly dried by dis 275 parts of methylene distearamide was mixed tilling it with benzene. The reaction mixture thoroughly with 60 parts of paraformaldehyde 20 was kept at the boil for twenty minutes and then and then gradually added to 500 parts of benzene cooled to room temperature, decolorized with which has been heated to' 60° C., while passing charcoal and ?ltered from the inorganic salts and into this reaction mixture a constant stream of the charcoal. The solution thus obtained was still ‘ hydrogen chloride. After a clear solution re slightly acid to Congo red paper and was neu . suited the reaction was continued for a few hours tralized by agitating the solution with some pow longer than the aqueous layer drawn'oif and the dered potassium carbonate, calcium oxide or any benzene evaporated under vacuum on the steam other basic compound capable of'neutralizing the bath. -. solution. »When a cotton or rayon fabric was im 62 parts of this residue were dissolved in 100 pregnated with an 0.5% solution of this product parts of benzene, and then 60 parts of slightly 30 in carbon tetrachloride, then subjected to a bak moist potassium thiocyanate we're added and the ing step at 150° C., after treated with some hot masswas agitated at room temperature for two water and ironed, the fabric was strongly water days. , ' repellent and did not lose this property upon The inorganic salts were ?ltered off and the washing or dry-cleaning. clear solution was evaporated in vacuo. 50 parts 35 Example 4 of a somewhat yellow oil were obtained, which solidi?ed to a rather brittle, low melting wax. 252 parts of octadecyl carbamate were dis The product contained 9.12% 'of- and solved in 1600 parts of benzene heated to 60° C., only 0.1% of chlorine. ' and a stream of hydrogen chloride was passed in. The calculated amount of . sulfur for 40 To this solution there was added, in the course of methylene di-(stearamidomethyl thiocyanate), 11/2 hours, 72 parts of paraformaldehyde. When C41H76O2N4S2, is 8.9%. The probable formula of all the formaldehyde has been added, the reac this product is: - tion was continued for one hour longer, then the aqueous layer was drawn 01f, and the benzene 45 solution was evaporated in vacuo on the steam ‘bath. The residue was dissolved in 100 parts of benzene and added to 160 parts of dry lead thio cyanate suspended in 300 parts of hot benzene. The reaction mass was kept vigorously. boiling '50 for twenty minutes then ?ltered while still warm When cotton cloth was impregnated with a. 'and then allowed to cool to room temperature 1% solution of this product ‘in carbon tetra and treated with 50 parts of potassium carbonate chloride and then heated to 150° C. for three for 16 hours. Finally the solution was treated minutes, the material was strongly water-re with 50 parts of calcium chloride for 5 hours and pellent and lost only ‘very little of this property 55 then ?ltered from the inorganic salts. The by washing the fabric with soap and hot water or orange colored residue contained 8.96% sulfur. by dry cleaning the fabric with organic solvents. When cotton or rayon fabrics were treated with a dilute solution of this product as in Ex Example 2 _. . ample‘- 3,>a permanently water-repellent fabric 74 parts‘ of methyIeneTdi-(stearamidomethyl 60 was obtained which had a soft feel. chloride) prepared as in Example 1 were dissolved “ : Example 5 in 80 parts of benzene and agitated with _6 parts Methyl stearamide was converted in known of barium carbonate for half an hour. manner to the chloromethylamide and then react 40 parts of ?nely pulverized potassium thio 65 ed with lead thiocyanate. This chloride ap cyanate was mixed with 1 part of water and then peared to be somewhat less reactive than those added to the above benzene solution. above, and the reaction mixture had to be heat After agitating the reaction mass for 16 hours ed to 80° C. for several hours to complete the re-‘ ‘ .it was almost neutral to Congo red paper. More. ‘action. The resulting thiocyanate imparted per benzene was added and the liquid was then ?l 70 manent water-repellency to cotton, when this tered o?? from the inorganic salts. Upon evapora was impregnated with a 1% solution in trichloro tion of the solvent, a slightly yellow wax re ighylene and then heated for several minutes to mained which analyzed as follows: 0° C. Example 6 . ‘ Nitrogen 7.28% S (llglcgulated for CaH7,0,N4S,:N-=7.8 ‘ Snlfur,7.76% 75 90 parts of stearamide were dissolved in 500 4 2,881,276 parts of benzene and then, gradually, 26 parts of the acid chloride with phosphorus trichlorlde. paraformaldehyde were introduced, while pass The crude reaction product, which was freed from ing a slow stream of hydrogen chloride through excess acids by placing the material under the reaction mass at, 60° C. After a_few_hours, vacuum and warming the charge, was dissolved a clear solution resulted; the water was sepa CI in benzene and then, over a period of one hour, ' rated and the benzene was evaporated. 43 parts of hexamethylene-tetramine were added To 100 parts of the oily residue obtained there while the charge was heated to 80° C. To the were added 66 parts of dry lead thiocyanate and almost clearv solution which resulted there were 200 parts of benzene, and then heated to the added 228 parts of lead thiocyanate, and the boil for thirty minutes replacing the benzene 10 mass was then again heated to the boil for which distills over with fresh, dry benzene. The twenty minutes, whereupon the inorganic salts slightly acid'solution was ?ltered, and neutralized were ?ltered out. ‘The resulting slightly yellow - by stirring for 2 hours with 5 parts of potassium ish solution was neutralized with 30 parts of carbonate and ?nally dried with calcium chlo potassium carbonate and again ?ltered. Upon ride and ?ltered again. A very faintly yellowish evaporation, a low melting hard solid remained solution was obtained. which contained essentially one sulfur atom and When this product was applied from a very two nitrogen atoms per long fatty chain. dilute solution (0.2%) to cotton or rayon then Cotton and rayon pieces were impregnated with subjected to a baking treatment for 20 minutes a solution of this product in carbon tetrachloride at 150° C. a strongly water-repellent ?ber was containing 1% of the active ingredient and then obtained. heated for a few minutes to 140° C. The ma In place of stearamide an equivalent amount terial became strongly water-repellent. This re of palmitic acid amide, montanic acid amide, oc pellency was noticeably increased when the goods tadecyl-urea or stearoyl urea may be used. were wetted out in hot water and ironed. Example 7 25 A similar result was obtained by using thionyl chloride in the initial stages of the process in A 30% solution in benzene of the product pre lieu of phosphorus trichloride, but the ultimate pared according to Example 4_ was mixed with product was darker. Both products, when half of its ‘volume of pyridine and then allowed treated with pyridine, gave a water-soluble to stand at room temperature for three days. By 30 quaternary compound. this time a considerable amount of a crystalline Instead of lead thiocyanate in the above ex product separated from the solution. ' It was ?l amples, calcium thiocyanate, sodium thiocyanate tered o? and gave in warm water a very viscous or any other commonly available inorganic salt clear solution. of thiocyanic acid may be employed. This product is the quaternary pyridinium' It will be understood that the details of the thiocyanate. The benzene solution obtained above examples may be varied further within ‘from the above ?ltration was evaporated in vacuo wide limits without departing from the spirit of and also dissolved to a clear solution in water. this invention. When cotton cloth was impregnated with a 1% It will be understood that the theory advanced aqueous solution of this pyridine compound and’ 40 hereinabove concerning the isomerization of the heated for a few minutes to 120 to 150°C. a thiocyanates is hypothetical and shall not be strongly water-repellent material was obtained taken as a limitation upon the scope of this in which was not noticeably impaired by a washing vention. This theory is based on the observation process. ' that a benzene solution of stearamido-methylene If in the above reaction pyridine was replaced 45 thiocyanate or of octadecyl-carbamido-methyl by trimethylarnine a similar reaction occurred. ene-thiocyanate will readily react with pyridine The resulting product had similar properties to when only a day, or two old, to give completely the pyridlnium compound. It gave clear, viscous water-soluble compounds with properties which solutions in water, decomposed with alkalies, and justify the conclusion that that they are quater rendered ?brous material water-repellent. 50 nary ammonium compounds. Upon standing, Example 8 however, these solutions lose partially or com To 50 parts of a 38% solution in benzene of the‘ pletely the power of reacting with pyridine. Ac product secured according to Example 6, 25 parts ‘ cording to my theory, this loss of reactivity to ward pyridine is due to rearrangement into the of pyridine were added, and the mixture was al 55 lowed to stand over night. After evaporation of corresponding isothiocyanates. But exhaustive the benzene, the product was clearly soluble in research data are not available, and it would water,.giving viscous foaming solution. With the be‘ di?icult to determine the correctness of the above theory absolutely, at this time. aid of some methyl alcohol the amorphorous - Fortunately, however, such theory is not es product started to crystallize. 60 sential to the practical utility of this invention. Cotton jean cloth was impregnated with a 1% I have found that the product is soluble in or- . aqueous solution of this product, and dried in ganic ‘solvents, for instance benzene or carbon the air, then heated for a few minutes to 120 to 150° C. A strongly water-repellent cloth was ob tetrachloride, at any stage, and that such solu tained without impairing the tensile strength tion is capable of endowing textile fabric, especi ally cellulose, with water-repellent qualities to a noticeably. V ' When in the above experiment pyridine was very high degree. Evidently, the thio-compounds replaced by trimethylamine, a similar reaction and the isothio-compounds are equivalent in occurred, yielding a product which was soluble these respects, and hence the degree‘ of conver in water and had the property of imparting 70 sion of one into the other has no appreciable ef permanent water-repellency to ?brous materials feet on either the or the water-repel when heated to ‘a high temperature. lency powers of the mixture. For use as water-repellents, the novel prod Example 9 ucts of this invention have the advantage that 280 parts of stearic acid were converted into 78 they do not liberate acid in the baking step, or 5 2,881,276 a salt of thiocyanic acid upon the N-methylene else probably liberate some unstable acids which halide of an organic amide having an aliphatic decompose quickly and are evaporated. Conse chain of at least '1 carbon atoms, whereby to ef quently there is no appreciable tendering of the fect condensation between the two compounds ?ber,- and the addition of bu?ers to’ the treat with elimination of a metal halide. ment bath is not needed. 9. The process of preparing novel organic com Iclaim: positions of matter, which comprises condensing 1. A compound of the group de?ned by the a metal thiocyanate with a halogen compound as formulas . de?ned below,‘ with elimination of the corre , R-Y-NH-OHr-Q sponding metal halide, said halogen compound 10 R-Y-N-CHa-Q being one selected from the group consisting of I the methylene halides represented by the for mulas

II 15

R-Y-hI-CHr-Q and aliphatic radical con- _ wherein R stands for an R-Y-N-CHz-X taining at least '7 carbon atoms and being free of water-solubilizing groups; Y is a link selected 20 II from the group consisting of CO, O—-CO, NH-CO, CO-NHCO and O—C0—NHCO; Q is wherein R is an aliphatic radical containing at a radical of the group consisting of the thio least 7 carbon atoms in its structure but being cyanate radical and the isothiocyanate radical, free from water-solubilizing groups, Y is a link while R’ and R" are respectively lower alkyl and selected from the group consisting of CO, 0-00, lower alkyiene radicals. NI-I-CO, CO-NHCO, and O-—CO—NHCO, X is 2. A'compound of the formula halogen, while R’ and R" are respectively lower alkyl and lower alkylene radicals. _ 10. The process of preparing novel organic com wherein Alk stands for-an alliyl radical having 30 positions of matter, which comprises reacting with from 7 to 36 carbon atoms in its structure, while a salt of thiocyanic acid upon a methylene chlo Q is a radical of the group consisting of the thio cyanate radical and the isothiocyanate radical. ride compound of the general formula 3. A compound of the formula wherein Alk stands for an alkyl radical having wherein Alk stands for an alkyl radical having from 7 to 36 carbon atoms in its structure, where from '7 to 36 carbon atoms in its structure, while by to effect condensation between two compounds with elimination of a metal chloride. Q is a radical of the group consisting of the thic 11. The process of preparing novel organic cyanate radical and the isothiocyanate radical. 40 compositions of matter, which comprises react 4. A compound of the formula ing with a salt of thiocyanic acid upon a methyl Aik-C 0-—N—-C HPQ ene chloride compound of the general formula _ CH: Alk—-O-—-CONH--CH2C1, wherein All: stands Alk—C O—1lI——GHr—Q for an alkyl radical having from 7 to 36 carbon 'atoms in its structure, whereby to effect con wherein Alk stands for an alkyl radical having densation between said two compounds with from '7 to 36 carbon atoms in its structure, while elimination of a metal chloride. Q is a radical of the group consisting of the thio 12. The process of preparing novel organic cyanate radical and the isothiocyanate radical. compositions of matter, which comprises react 5. A compound selected from the group con ing with a salt of thiocyanic acid upon a methyl sisting of stearamido-methylene-thiocyanate and ene chloride compound of the general formula the corresponding isothiocyanate. Alk-C O—N—-CH:C1 6. A compound selected from the group con sisting of octadecyl—carbamido-methylene-thio 7 Ha cyanate and the corresponding isothiocyanate. Alk-C O—N——CHzCi 7. A compound selected from the group con~ wherein Alk stands for an allgyl radical having sisting of N,N’ - methylene - bis - (stearamido from '7 to 36 carbon atoms in its structure, where methylene-thiocyanate) and the corresponding by to effect condensation between said two com bis-isothiocyanate. 0 pounds with elimination of a metal chloride. 8. The process of preparing novel organic. com. 6 J OSEF PIKL. positions of matter, which comprises reacting with mansions 0F conmacnou. Patent No. 2,531,276. ~ October 5, 191g. JOSEF PIKL. It is hereby certified thaterror appears in the printed specification of the above Jmmbered patent requiring correction as follows: Page 1, sec ond column, line 1, for "alkylamino" read --a1kylimino—-; page 5, second. column, line 58, claim 10, before the wordy'two" insert -'-said.-—; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office. Signed and sealed this 25rd day of November, A. D. 1914.5.

Henry Van Arsdale, (Seal) Acting Commissioner of Patents.