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UNITED STATES PATENT OFFICE MONO-ACYL ETHYLENE DIAMINES : Nathan Weiner, West Forest Hills, N.Y., Assignor to Bonneville, Limited, New York, N

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UNITED STATES PATENT OFFICE MONO-ACYL ETHYLENE DIAMINES : Nathan Weiner, West Forest Hills, N.Y., Assignor to Bonneville, Limited, New York, N Patented Oct. 16, 1945 2,387,201 UNITED STATES PATENT OFFICE MONO-ACYL ETHYLENE DIAMINES : Nathan Weiner, West Forest Hills, N.Y., assignor to Bonneville, Limited, New York, N. Y., a cor poration of Delaware . No Drawing. Application January 12, 1942, Serial No. 426,487 8 Claims. (C. 260-404.5) This invention relates to new derivatives of solvent to recover the mono-acyl ethylene ethylene diamine and more particularly it relates diamine. to new mono-acyl derivatives of ethylene diamine. The amount of ethylene diamine reacted with a The invention includes new mono-acyl ethylene given quantity of an ester is advantageously a diamines as Well as a new process for making 5 substantial excess over the amount needed to these compounds. form the mono-acyl derivatives; for example, The new compounds of the invention are mono about four to six or more moles of the diamine are acyl ethylene diamines containing from 12 to 14 used for each mole of fatty acid residue in the carbon atoms in the acyl group and include mono ester. Thus, with the ester of a triglyceride about lauroyl and mono-myristoyl ethylene diamines. O 12 to 18 moles of ethylene diamine are advan The invention also includes mixed mono-acyl tageously used per mole of triglyceride. ethylene diamines in which the acyl group is de The reaction between the ethylene diamine and rived from the fatty acids obtainable from natural the ester of tne fatty acid is advantageously car oils and waxes which contain a major proportion ried out at temperatures of about 80° to 100'. The of fatty acids in the free or combined state hav 5 length of time for the reaction varies, depending ing from 12 to 14 carbon atoms, such as, for ex upon the particular ester used in the reaction. It ample, the fatty acids obtainable from bayberry may take as much as four, five, or six hours be Wax, palm kernel oil, and cocoanut oil. fore the reaction is complete. The new mono-acyl ethylene diamines are The fatty acid esters may be in the form of Solids of characteristic melting point, with 20 esters of mono- or polyhydric alcohols such as, strongly basic properties as exemplified by their for example, methanol, ethanol, glycol, glycerol, ability to form characteristic amine hydrochlo etc. Thus, for example, such esters as methyl rides. or ethyl laurate or myristate may be used with The invention also includes the salts of the advantage. To produce acyl derivatives of ethyl aforementioned mono-acyl ethylene diamines, as 25 ene diamine Such esters as bayberry wax, palm Well as a process by which such salts may bead kernel oil, or Cocoanut oil may be used with ad Vantageously prepared. Such salts may be pre Vantage, all of these materials containing a major pared in accordance with the invention, by dis proportion of polyhydric alcohol esters of lauric Solving the mono-acyl ethylene diamine in a sol and myristic acids. These mixed acyl derivatives vent in which the salt desired is substantially in 30 will hereinafter be named by reference to the oil soluble, e. g., ether, ispropyl ether, benzene, tolu or fat from which the compound has been de ene, etc., and then treating the resulting solution rived; thus the acyl derivative produced from of the mono-acyl ethylene diamine with a sub bayberry Wax and ethylene diamine will be called stantially anhydrous acid corresponding to the bayberry Wax-ethylene diamine, etc. Salt desired, e.g., hydrochloric, hydrobromic, sul In carrying out the process of the invention phuric, etc., to produce the chlorides, bromides, both mono-acyl ethylene diamines and di-acyl Sulphates, etc., respectively. These salts are ethylene diamines are produced, the amount of water Soluble and have very desirable surface the latter present in the reaction products being activity characteristics. They may advan relatively small. In general, the yield of the tageously be used as emulsifying, detergent, wet 40 mono-acyl compound is about 80% or higher, ting, dispersing, or flotation agents; and, in the based on the ester, the remainder of the ester form of the hydrochloride Salts, they may be used being converted to the di-acyl derivative. To de With particular advantage as flotation agents in Crease the amount of di-acyl derivatives formed, the froth flotation of potassium chloride ores or the process of the invention may advantageously brines. 45 be modified by adding to the initial reaction mix The new process of the invention by which the ture a di-acyl derivative of ethylene diamine hay new mono-acyl ethylene diamine derivatives may ing the same acyl groups as in the mono-acyl be produced comprises heating an excess of derivatives which it is desired to produce. Ad ethylene diamine with an ester of a fatty acid vantageously the amount of the di-acyl derivative containing from 12 to 14 carbon atoms, treating 50 added is substantially equal to that which would the reaction mixture With a water-immiscible sol be produced in the reaction if no di-acyl deriva went for the mono-acyl ethylene diamine, sepa tive Was added initially. If the process of the rating the water-immiscible Solvent containing invention is carried out in this way the amount the mono-acyl ethylene diamine dissolved therein of di-acyl ethylene diamine produced in the re from the reaction mixture and evaporating the 55 action Will be practically negligible, with the re 2 2,387,201 sult that greater yields of the mono-acyl deriva in which natural oils or waxes containing a tives will be obtained. major proportion of esters of fatty acids having In practicing the process of the invention any from 12 to 14 carbon atoms are used. In these suitable water-immiscible solvent for the mono examples the mixed acyl ethylene diamines are acyl ethylene diamine may be used, such as, for converted directly to the hydrochlorides without example, ether, di-ethyl ether, di-propyl ether, Separation of the diamine from the Water-in butyl ether, benzene, toluene, xylene, chloroform, miscible layer in which it is recovered from the carbon di-sulphide, etc. In these Solvents, the reaction mixture. di-acyl ethylene diamines and the ethylene di ExAMPLE 3 . amine are insoluble or SO slightly soluble as not O to interfere with the recovery of substantially Cocoanut oil ethylene diamine hydrochloride pure mono-acyl ethylene diamines therefrom. About 1000 grams of cocoanut oil and 2000 The new process of the invention will be illus grams of 70% ethylene diamine are stirred to trated by the following examples, but it is not gether vigorously at about 95° C. for about five limited thereto. 5 hours. The resulting almost homogeneous mix EXAMPLE 1. ture is cooled to about 50 C. Enough ether to a. give about 10 liters of solution is then added and Mono-lauroyl ethylene diamine the Solution further cooled to room temperature, One mole of methyl laurate is mixed with . The insoluble slush of di-acyl ethylene diamines about six moles of 70% ethylene diamine and 20 is then separated by filtration. The ether-in Stirred at about 100' C. for about four hours. Soluble layer of the filtrate is separated from the The resulting suspension of solid and viscous ether layer which is then concentrated to about liquid is cooled, with stirring to keep the solid 4 liters. Dry hydrogen chloride gas is then finely divided. Ether is then added and the mix passed through the ether solution until the sepa ture is thoroughly stirred. At this stage the mix 25 ration of mixed mono-acyl ethylene diamine ture consists of a solid phase and two layers of hydrochlorides ceases. The solid is then sepa liquid, one being an aqueous solution of ethylene rated by centrifuging. It has a melting point diamine and the other an ether solution of mono of about 45-55 C. EXAMPLE 4 lauroyl ethylene diamine. The solid phase is 30 filtered from the mixture and washed with ether. Palm kernel oil ethylene diamine hydrochloride It consists of dilauroyl ethylene diamine having 1000 grams of palm kernel oil and 2000 grams a melting point of 162-164 C. The filtrate is of 70% ethylene diamine are treated by the separated into the lighter ether layer and the process described in Example 3 to produce the heavier ethylene diamine layer. The excess 35 hydrochlorides of mixed mono-acyl ethylene di ethylene diamine is recovered from the latter by amines in which the acyl groups are those origi distillation. The ether layer on evaporation nally present as the acids of the triglycerides of leaves mono-lauroyl ethylene diamine having a palm kernel oil. The palm kernel oil ethylene melting point of 5-52 C. diamine hydrochloride has a melting point of EXAMPLE 2 40 about 45–55° C. t Mono-maristol ethylene diamine ExAMPLE 5. One mole of methyl myristate and one-fifth Baaberry Daac ethalene diamine hydrochloride mole of di-myristoyl ethylene diamine are mixed 1000 grams of bayberry wax and 2000 grams of with about 5.6 moles of 70% ethylene diamine 45 70% ethylene diamine are treated by the process and stirred at 100 for about three hours. The described in Example 3, to yield a mixture of resulting suspension of solid and viscous liquid mono-acyl ethylene diamine hydrochlorides con is cooled with vigorous stirring to keep the solid sisting principally of the hydrochlorides of mono finely divided. Sopropyl ether is then added lauroyl ethylene diamine and mono-myristoy and the mixture is thoroughly stirred. The di 50 ethylene diamine. The bayberry wax etnylene myristoyl ethylene diamine in the reaction prod dianine hydrochloride has a melting point of uct is separated from the reaction mixture by about 50-55° C.
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