Patented Dec. 15, 1942 2,305,083 UNITED STATES PATENT OFF ICE 2,305,083 AMNO ALCOHOL ESTERS David Walker Jayne, Jr., Old Greenwich, and Harold Milton Day, Cos Cob, Conn., assignors to American Cyanamid Company, New York, N. Y., a corporation cf Maine No Drawing. Application March 22, 1940, Serial No. 325,394 11 Claims. (C. 260-401) The present invention relates to the fatty acid to limit the invention by such a positive desig esters of Sulfonic acid salts of primary amino nation and prefer therefore to , broadly include alcohols and to a process of preparing them. any or all products produced by the reaction of The ordinary methods of producing carboxylic either aliphatic or aromatic sulfonic acid salts acid esters of amino alcohols having at least one of amino alcohols having at least one primary primary or secondary amino group frequently or secondary amino group with fatty acids. The do not run smoothly and particularly when the preferred fatty acids are those containing at carboxylic acid employed is a high-boiling or a least 8 carbon atoms and especially the fatty long-chain fatty acid. For example, if an amino acids of animal and vegetable origin which con alcohol such as a mono- or di-ethanolamine is O tain at least 10 carbon atoms. The fatty acids heated with a fatty acid, the ethanolamide of may be either saturated or unsaturated and may the fatty acid rather than the amino ethylester or may not be hydroxylated. results. Some of these difficulties have been The reaction products of the sulfonic acid overcome in the past by employing amino alcohol salts of amino alcohols and the higher fatty salts of relatively strong acids. This type salt, acids of the present invention are useful as wet however, is not at all suitable for the prepara ting agents, detergents, emulsifying agents, dis tion of the esters of fatty acids and particularly persing agents and flotation reagents, particu the high boiling fatty acids. When the amino larly as promoters in the flotation of acidic alcohol is used in the form of a salt of a mineral silicious gangue. Many of the compounds are acid or a relatively strong carboxylic acid, it is 20 Soluble in the common aliphatic and aromatic not compatible with the higher fatty acid or hydrocarbons which very greatly increases their it produces a volatile acid on heating. For ex usefulness. ample, a fatty acid such as myristic acid and a The fatty acid esters of the sulfonic acid salts mono- or di-ethanolamine hydrochloride, sul of amino alcohols of the present invention may fate, phosphate, etc. are not compatible and at 25 also be utilized for the production of fatty acid tempts to prepare esters by direct heating of esters of amino alcohols, by treatment of the Such a mixture or refluxing in an organic sol ester salts with a suitable alkali. The fatty acid vent, with esterification catalysts, are not suc esters So produced are free from contamination cessful due to this extreme incompatibility. with amides and many of the difficulties of the When myristic acid and a mono- or di-ethanol 30 prior methods are eliminated. - amine acetate are heated together, the acetic acid The following examples are further illustra is driven off and the amide of myristic acid tions of the present invention, but the inven is formed instead of the ester. tion is not restricted thereby. The parts are In accordance with the present invention we given by weight. have found a process in which sulfonic acid salts EXAMPLE 1. of amino alcohols having at least one primary or secondary amino group are reacted with car Reaction product of capric acid and boxylic acids to produce the esters thereof. The monoethanolamine p-toluene sulfonate reaction proceeds smoothly between either the 125 parts of p-toluene sulfonic acid.H2O was aliphatic sulfonic acid Salts or aromatic sulfonic 4) added to 40 parts of monoethanolamine. To the acid salts of Such amino alcohols with fatty resulting salt was added 108 parts of technical acids. In the preferred embodiment of the pres capric acid and the mix heated slowly to 250° C., ent invention, however, the aromatic sulfonic with evolution of steam, and then cooled to room acid salts of straight chain primary amino al temperature. The product was a thick, dark cohols are reacted with higher fatty acids. These colored paste which was completely soluble in preferred compounds are entirely compatible and water. the esters are produced by heating mixtures of EXAMPLE 2 the substances to about 200-250° C. whereupon Reaction product of lauric acid and water is split out and the fatty acid ester of monoethanolamine p-toluene sulfonate the aromatic Sulfonic acid salt of the amino 50 alcohol is formed. For example, if a mixture The same procedure was followed as in Ex of 30 grams of the p-toluene sulfonic acid salt ample 1 using 25 parts of p-toluene sulfonic of mono-ethanolamine and 30 grams of myristic acid.H2O, 8 parts of monoethanolamine and 26 acid (1:1 molar ratio) is heated in an open parts of technical lauric acid. The product was beaker to 250° C. A light brown soft waxy ma- :5 5 a thick, dark-brown paste which was completely terial is obtained which is completely soluble in soluble in water. water, to give 'soapy' solutions which have wet EXAMPLE 3 ting-Out, emulsifying, and dispersing properties. Reaction product of myristic acid) and While the compounds of the present inven. monoethanolamine p-toluene sulfonate tion are most probably esters we do not desire The same procedure was used as described in 2 2,805,083 Example 1 using 25 parts of p-toluene sulfonic amine, and various other alkyl amino alcohols acid.H2O, 8 parts of monoethanolamine and 30 Such as: parts of technical myristic acid. The product 2 methyl 2 hydroxyl amino propane was a light brown, soft wax which was completely 2 methyl 2 hydroxy 4 aminobutane soluble in water. 5 2 methyl 2 hydroxy 5 amino pentane EXAMPLE 4 2 mehyl 2 hydroxy 6 amino hexane Hydroxyethyl ethylene diamine Reaction product of coconut oil fatty acids and 2 amino 1 butanol monoethanolamine p-toluene sulfonate 2 amino 2 methyl 1 propanol The same procedure was followed as in Ex 10 2 amino 2 methyl 1,3 propanediol ample 1 using 50 parts of p-toluene sulfonic 2 amino 2 ethyl 1,3 propanediol acid.HaO, 16 parts of ethanolamine and 54 parts Tri (hydroxymethyl) amino methane of coconut oil fatty acids. The product was a or any amino alcohol or derivative thereof hav thick, dark-colored paste which was completely ing at least one primary or secondary amino soluble in Water. group capable of forming a salt with an organic EXAMPLE 5 Sulfonic acid and at least one hydroxy group capable of forming an ester with a carboxylic Reaction product of Capric acid and monoeth acid. anolamine ben2eme sulfonate We claim: 1. A process of producing chemical compounds The same method as employed in Example 1 which comprises reacting at elevated tempera. was used, and 61 parts of benzene sulfonic acid, tures organic sulfonic acid salts of amino alco 23 parts of monoethanolamine, and 65 parts of hols having at least one member of the group technical capric acid were reacted together. The consisting of primary and secondary amino product was a dark brown, viscous liquid which 2 5 groups and having at least one free hydroxy was completely soluble in water. group with higher fatty acids. EXAiPLE 6 2. A process of producing chemical compounds which comprises reacting at elevated tempera Reaction product of capric acid and diethanol tures aromatic sulfonic acid salts of aminoalco amine p-toluene sulfonate () hols having at least one member of the group A process similar to that employed in Example consisting of primary and secondary amino 1 was used and the reaction carried out with 100 groups and having at least one free hydroxy parts of p-toluene sulfonic acid.H2O, 50 parts group with fatty acids having at least 8 carbor of diethanolamine and 190 parts of technical atoms. capric acid (molecular ratio 1:1:2). The prod 3. The higher fatty acid esters of organic sui uct was a water soluble, dark-colored viscous liq fonic acid salts of amino alcohols having at lease lid. one of the radicals of the group consisting of Other carboxylic acids which may be used in primary amino radicals and secondary amino place of all or part of the acids in the above ex 40 radicals. amples are caproic, palmitic, stearic, oleic, ablet 4. Higher fatty acid esters of organic sulfonie ic, montanic, napthenic acids, talloil acids, mix acid Salts of amino alcohols having at least one tures of such acids and especially mixtures of . primary amino group. acids obtainable by Saponification from coconut 5. Higher fatty acid esters of organic sulfonic oil, palm kernel oil, cotton seed oil or from any 45 acid Salts of amino alcohols having at least one of the various other vegetable or animal oils and Secondary amino group. fats, w 6. Higher fatty acid esters of aromatic sulfonic Likewise various other organic sulfonic acid acid salts of amino alcohols having at least one Salts of amino alcohols having at least one pri of the radicals of the group consisting of primary mary or secondary amino group may be used in anino radicals and secondary amino radicals. . place of all or part of those in the above exam 7. Higher fatty acid esters of aromatic sulfon. ples and the invention is not limited to those ic acid salts of amino alcohols having a primary of a particular series. Thus, for example, in ad amino group. - dition to the common aromatic sulfonic acids of 8. Higher fatty acid esters of aromatic sui the benzene series employed in the examples 5 5 fonic acid salts of amino alcohols having a sec those of diphenyl, napthalene, anthracene, phen Ondary amino group. anthrene Series may be used. The aliphatic sul 9. Higher fatty acid esters of p-toluene sul fonic acids may likewise be employed such as fonic acid salts of amino alcohols having at those of paraffin hydrocarbons of 12-18 carbon least one of the radicals of the group consist atoms in length, ligninsulfonic acid, guanyl urea, 60 ing of primary amino radicals and secondary sulfonic acid, dodecyl sulfonic acid and the like, amino radicals. also compounds such as toluene thiosulfonic acid. 10. Higher fatty. acid esters of p-toluene sul Representative amino alcohols which may be fonic acid salts of amino alcohols having a pri employed in preparing the Organic sulfonic acid mary amino group. salts in addition to those of the above examples 11. Higher fatty acid esters of p-toluene sul and which may be used in place of all or part fonic acid salts of amino alcohols having a sec thereof are: monopropanol amine, dipropanol Ondary amino group. amine, mono isopropanol amine, diisopropanol DAVID WALKER JAYNE, JR. amine, monobutanol amine, mono isobutanol HAROLD MILTON DAY.