Patented Jan. 25, 1938 2,106,181

UNITED STATES PATENT OFFICE 2,106,8. ETHYNY, CARBNOELS AND PROCESS OF PRESPARENG TEESAME Oscar Robert Kreimeier, Woodstowgli, N. S., as signor to E. E. du Font de Nemours & Company, Wilmington, Elbe, a corporation of Delaware No Drawing. Application July 20, 1936, Seria. No. 9623 0 Claims. (C. 269-156) ihis invention relates to alcohols prepared ther object is the provision of new ethynyl from aldehydes and alkali metal acetylides, and carbinols. Other objects will appear hereinafter. to a process for preparing them. More partic These objects are accomplished by the follow ularly, it relates to a process for preparing pri ing invention which consists in reacting an al Inary and Secondary alpha-ethynylcarbinols kali metal with an excess of liquid ammonia in from aldehydes and very soluble and reactive the presence of an alkali metal oxide and of an forms of alkali metal acetylides in solution in ammonia-soluble hydrated Salt of a ferrous metal, reacting the solution of alkali metal amide liquid ammonia. thus formed with acetylene, and finally reacting Several methods for the preparation of O 0. ethynylcarbinols have been reported in the lit the resulting alkali metal acetylide in situ. With erature but all of them are objectionable, chief an aldehyde. All three steps are carried out ly because of poor yields, but also because of in liquid ammonia as one continuous proceSS. difficulty in controlling the reactions, use of in Sodium is a typical alkali metal, sodium oxide flammable solvents such as ether, or the unsat a suitable alkali metal oxide, ferric nitrate en 5 5 isfactory Sclubility of the reactants and prod neahydrate a typical hydrated ferrous metal lucts in the reaction media. Of the methods salt, and acetaldehyde a typical aldehyde. which have been employed, one which has found I have found that primary and secondary considerable favor is the reaction of an alkali ethynylcarbinols can be obtained in excellent metal acetylide with aldehydes or ketones, foll yields and in a high state of purity by reacting 20 Twed by hydrolysis of the product to liberate the aldehydes with a reactive and soluble variety 20 free ethynylcarbinol. These reactions have of sodium or other alkali metal acetylide which heretofore been conducted either in the absence is used in solution in the liquid ammonia, in of a solvent or reaction medium, or in dry ether which it is formed and which is in turn prepared Cr liquid ammonia. The procedure employed from a reactive and soluble variety of Sodamide. has been to dissolve or suspend the preformed The preparation of this sodamide, which 25 alkali metal acetylide in the reaction medium, to forms the first step of the present invention, is add the desired carbonyl compound thereto and, described by Vaughn, Vogt and Nieuwland after reaction has taken place, to isolate the (J. A. C. S. 56, 2120-2122 (1934), and consists in ethynylcarbinol by conventional means. reacting sodium with excess liquid ammonia in 30 The alkali metal acetylides heretofore emi the presence of catalytic proportions of Sodium 30 ployed for reaction with aldehydes have been oxides and of ammonia-soluble, hydrated salts prepared (1) by reacting the alkali metal With of iron, cobalt or nickel (herein termed "ferrous acetylene in a Suitable relation medium such metal salts'). The second step of the inven as liquid ammonia, dry ether or benzene, or tion, also mentioned by Vaughn, Vogt and Nieuw (2) by reacting acetylene with an alkali metal land, is to react the sodamide in situ (i. e., with 35 amide in liquid ammonia, dry ether or other suit out isolating it from the liquid ammonia in which able reaction medium. The first method has it is formed) with acetylene to form sodium not been practiced to any great extent because acetylide of a variety which is particularly re active. The third and final step of the in of undesirable side reactions such as polymeri 40 40 zation or hydrogenation of some of the re vention, which is also new in itself, is to re actants, whereby yields are reduced and the act the sodium acetylide in situ with the se products contaminated. The second method, lected aldehyde. In this last step, the reaction i. e., the use of alkali metal amides has hereto is usually complete within about four hours. The fore been open to three objections, namely: ammonia is then evaporated off, the residue is 45 45 alkali metal amides, being unstable, are incon treated with water, and the resulting solution venient and expensive to prepare and store; they or suspension is acidified to liberate the ethynyl have not been sufficiently soluble in reaction carbino. media such as liquid ammonia; and the partic Aikai metal amides prepared with the cata ular types of alkali metal amides heretofore lysts just given are more soluble in liquid am used react very slowly and the yields of alkali monia and more reactive than alkali metal amides 50 metal acetylides have consequently not been ' prepared by other methods. The greater solu good. bility and reactivity are impaired or lost if the This invention has as an object the provision alkali metal amides are isolated from the liquid of a new process for the preparation of primary ammonia in which they are formed. 55 55 and secondary alpha-ethynylcarbinols. A fur Having thus outlined the principles and pur 2 2,106,181 poses of the invention, the following exemplifi uid ammonia was prepared as in Example I, parts cations, wherein all parts are parts by weight, are A and B. Two (2) mols (144 parts) of isobutyr added in illustration and not in limitation. aldehyde were added to the solution at -60 to -50° C. With stirring over a period of thirty min EXAMPLE. I.-PROPARGYL ALCOHOI utes. The reaction mixture was stirred for four A. Preparation of sodamide hours, after which time the ammonia, was allowed One (1) part of sodium was added to a me to evaporate. The residue was dissolved in 300 chanically stirred mixture of 0.3 part of finely parts of water, and sufficient acetic acid WaS powdered ferric nitrate enneahydrate added to make the solution acid to litmus. The 0. water-insoluble layer was separated, the Water 0 layer extracted twice with 70 parts of ether, and in 385 parts of liquid ammonia, contained in a the extracts combined with the main fraction, reaction vessel of about four times the volume of which Was then dried and distilled. The main the liquid ammonia used. Air was bubbled fraction consisted of a straw-colored liquid, boil 15 through the solution (to-form oxides of sodium in ing at 130°-133° C. and somewhat soluble in the reaction mixture) until the blue Color was water, which was identified as isopropylethynyl discharged, and 46 parts (2 mols) of sodium were carbinol. The yield was 168 parts, or 81% of then added in small pieces. The reaction set in theory. at once and in ten to twenty minutes the blue EXAMPLE W.-HEPTYLETHYNYLCARBINOL 20 20 color changed to gray, indicating the end of the A solution of 246 parts of alpha-ethylhexanal, conversion. Any suspended catalyst may be re dissolved in three times its volume of dry ether, moved by filtration. was reacted with a solution of 96 parts of sodium B. Preparation of sodium acetylide acetylide in liquid ammonia prepared as in Exam ple I. The reaction product was isolated in Sub 25 Acetylene was purified by passing successively stantially the same manner as described in Ex through 10% sulfuric acid, through 10% sodium ample IV. It was a water-insoluble liquid, boil hydroxide, through a trap cooled in a Solid carbon ing at 120°-122° C. at 55 mm., and was identi dioxide-methanol bath, and finally through cal fied as heptylethynylcarbinol, a compound of the cium chloride drying towers. From the calcium 30 chloride towers, it was passed rapidly into the formula 30 liquid ammonia Solution of Sodamide prepared CH3-CH2-CH2-CH2 as described above, until the color of the solution - CH(C2H5)-CHOH-C=CH changed from gray to black, the temperature of the reaction mixture being maintained at about The yield was 199 parts, or 67% of theory. -50° C. This change in color indicated that EXAMPLE WI.-IHEPTENYLETEIYNYLCARIBINOI, Sodamide had completely reacted with acetylene Ethylhexenal (216 parts), a compound of the to form sodium acetylide. formula CH3(CH2)2CHEC (C2H5). CHO boiling at C. Preparation of the carbinol 171-174° C., was reacted according to the meth od of Example V with a solution of 96 parts of 40 40 To the solution of sodium acetylide in liquid Sodium acetylide in liquid ammonia, the latter be ammonia, prepared as described under (B) ing prepared as in Example I. One hundred above, were added 60 parts of paraformaldehyde. forty-six (146) parts, or a yield of 56.2%, of hep The reaction mixture was stirred for four hours, tenylethynylcarbinol, a water-insoluble liquid after which time the ammonia, was allowed to boiling at 115-115.5° C./34 mm., was obtained. 45 evaporate. The residue was dissolved in 300 This compound has the formula, parts of water and enough acetic acid added to acidify the solution to litmus. The Solution was CH3-CH2-CH2CHEC (C2H5)-CHOH-CECH then steam distilled and the distillate Saturated with potassium carbonate. The non-aqueous EXAMPLE WII-ISOPROPENYLETHYNYLCARBINOL 50 layer was separated, dried, and distilled. The Equimolar quantities of methylacrolein and main fraction, boiling at 113°-115° C., was identi Sodium acetylide were reacted substantially as in fled as propargyll alcohol. Example I. Isopropenylethynylcarbinoi, B. P. EXAMPLE II-METHYLETHYNYLCARBINOL 141-144° C. and NE 1.4589, was obtained. EXAMPLE WIII.-OCTYLETHENYLCARBINOL 55 Following the procedure of Example I-C, 88 5 5 parts (2 mols) of freshly distilled acetaldehyde Equimolar parts of octaldehyde and sodium were reacted at -50 to -40° C. With an ammo acetylide were reacted as in Example I. Actyl nical Solution of 2 mols of sodium acetylide pre ethynylcarbinol, a syrupy liquid boiling at pared as in Example I, parts A and B. Eighty 120°-122 C./55 mm., was obtained in 67% yield. 60 two (82) parts or a 57% yield of methylethynyl An aldehyde or any mixture of aldehydes in 60 Carbinol, a colorless water-soluble liquid boiling general may be employed in the process of the present invention. Examples Of Suitable alde at 107-109 C., was obtained. hydes are formaldehyde, acetaldehyde, propion EXAMPLE III.-ETHYLETHYNYLCARBINOI, aldehyde, butyraldehyde, heptaldehyde, lauralde 65 Following the procedure of Example I-C, 116 hyde, Stearaldehyde, crotonaldehyde, acrolein, parts (2 mols) of propionaldehyde Were reacted citral (geranial), benzaldehyde, cinnamic alde with a liquid ammonia solution of 96 parts (2 hyde, and phenylacetaldehyde. The aldehyde mols) of sodium acetylide obtained as in Example may be aliphatic, aromatic, allicyclic or hetero I, parts A and B. Ninety (90) parts, or a 53.6% cyclic; it may be saturated or unsaturated; it 70 yield, of ethylenethynylcarbinol, a colorless water may have other functional groups such as car Soluble liquid boiling at 122-125 C., was ob boxyl; and it may be a mono- or polyaldehyde. tained. In the first step of my invention, I prefer to uSe Sodium and Sodium oxide because of their EXAMPLE IV.-ISOPROPYLETEIYNYLCARBINOL availability and economy. However, they may 5 A solution of 2 mols of sodium acetylide in liq be replaced wholly or in part by other alkali is 2,106,181. 3 metals such as lithium, potassium, rubidium, and metal may tend to act as a catalyst for the for caesium, and by their oxides. The oxide used as mation of the ethynylcarbinol in the presence of a catalyst may or may not be that of the metal excess aldehyde and acetylene. For example, reacted. Thus, sodium may be reacted with am yields considerably in excess of 100% based on the monia, which contains potassium oxide therein, alkali metal have been obtained in this way. and potassium may be reacted with ammonia The process is not limited to any particular pro which contains sodium oxide therein. It has portions of reactants in any one of the three steps, been found to be most convenient to use about i except that in the first step an excess of liquid

to 3%, based on the weight of the alkali metal, ammonia, must be used over that required to react O of the alkali metal oxide. The sodium or other with the alkali metal to form the alkali metal O alkali metal oxide is preferably formed in situ amide, and that in the second step there must as in the examples, since the addition of alkali be a sufficient excess of liquid ammonia, to dissolve metal oxide to the ammonia usually, introduces the alkali metal acetylide as it is formed. These alkali metal hydroxide which adversely affects the requirements are merely the necessary conse 5 desired reaction. While ferric nitrate enneahy quence of the use of liquid ammonia, as a single, 5 drate has been used to exemplify the second cata continuous solvent or reaction medium through lytic component, any ammonia-soluble hydrated out all the steps of the process. As illustrated in sat of a ferrous metal, i. e., of iron, cobalt or the examples, reacting equivalents of sodium nickel, may be employed. Thus, ferric chloride acetylide and aldehyde (i. e., 1:1 mol. ratios) 20 hexahydrate, ferric bromide hexahydrate, hy are preferred in the third step in order to 20 drated ferric acetate, hydrated ferric sulfate, fer minimize the formation of by-products. The ric nitrate hexahydrate and hydrated nitrates, invention, however, is not limited to such propor nitrites, cyanides, and thiocyanates generally of tions. For example, if a molecular exceSS of alde iron, cobalt and nickel may be employed. The hyde over the sodium acetylide is employed, mix 25 hydrated ferric nitrates are preferred. tures of products are obtained, viz., the mono 25 In the third step of the process, the aldehyde, hydric ethynylcarbinols together with more or less before it is added to the liquid ammonia, Solution of ethynyldicarbinols of the type of the alkali metal acetylide, may if desired first be dissolved in a suitable solvent such as dry R-C-Cs C-C-Ra, 30 ether, hydrocarbons, or liquid ammonia. This O O 30 expedient, however, is not generally necessary or where R1 and R2 may, for example, be hydrogen desirable. Any acid can be used to neutralize the or a monovalent hydrocarbon radical. When two reaction mixture containing the ethynylcarbinol. or more mols of aldehyde are used per mol. of Instead of the acetic acid of the examples, there sodium acetylide, as much as 50-70% of the prod 35 may be used such acids as formic, nitric and sul uct may be the dicarbinol, furic. As disclosed and claimed in Macallum, The ethynylcarbinols prepared as described Seria No. 969, filed of even date hereWith, an herein may be used for many purposes. For ex monium chloride may also be used in the neu ample, their esters with certain acids are useful tralization step. In Some cases, it is convenient as plasticizers and Solvents for natural or Synthet to isolate the ethynylcarbinols by extraction with ic resins, cellulose derivatives, etc. The carbinols 40 a Suitable solvent such as ether. In still other or their derivatives may also be employed as alco cases, the carbinols can be distilled from the alka holderaturants and as insecticides. Their metal line reaction mixtures without neutralization or lic derivatives may be used as anti-knock com extraction, pounds and fungicides. The carbinols may also 4. The reaction between the alkali metal and am be reduced to vinyl alcohols or to Saturated alco monia can be carried out conveniently at the boil hols, and can be hydrated to hydroxy-ketones. ing point of ammonia at normal pressure, i. e., They are also useful as modifying agents for resins about -33° C. By the use of pressure, the reac wherever alcohols are useful for this purpose. tion temperature may be raised, even up to the The process described herein is advantageous in critical temperature of ammonia, i. e., 132° C. that it makes possible the preparation of primary 50 Temperatures lower than -50° C. are not desir and Secondary ethynylcarbinols in better yields able due to the decreased speed of reaction. The than have heretofore been possible. The new remaining steps in the process may be carried out process avoids the difficulty, hazards, and expense similarly. Temperatures of about -50° C. to incidental to the isolation and storage of unstable 55 -30° C. and atmospheric pressure are preferred Compounds such as Sodamide and Sodium acety 55 throughout the entire process. At lower tempera lide, and to redissolving or dispersing them in liq tures, the Solubility of the alkali metal acetylide uid ammonia or other reaction media when they in liquid ammonia is reduced, and at higher ten are to be used for the preparation of ethynylcar peratures it has a tendency to induce polymeriza binols, since in this process the compounds are 60 tion of the aldehyde. w prepared only when and as needed. Moreover, 60 Elevated pressures are advantageous when Op the low temperatures at which the reactions are erating at temperatures above the atmospheric carried out minimize polymerization of the re boiling point of ammonia inasmuch as they en actants or of the products, thus promoting better able the ammonia, to be kept in the liquid state. yields and avoiding undesirable by-productS. 65 The time required in the third step for reacting OWing to the fact that the reactants and products the aldehyde with the alkali metal acetylide Will are all readily Soluble in liquid ammonia, none of vary with the aldehyde used and may range from the difficulties are encountered which are inciden one to several hours. The reaction is ordinarily tal to the tise of Suspensions Such as are neces completed after four hours, but it may n many sary when the reactants are only slightly soluble 70 instances be extended With advantage to five in the reaction medium, i.e., the reaction mix 0. hours or more, higher yields being obtained there tures remain liquid, do not Settle, are easy to by. This feature of the process is discussed in handle, stir, pump, etc. An additional advantage more detail in Macallum, Serial No. 91,619, filed arising out of the greater solubility of the react of even date herewith. The latter application also ants in liquid ammonia is that they are brought 75 shows that with longer reaction periods the alkali into more intimate contact with each other and 75 4 2,108,181 therefore react more readily-and completely. The of liquid ammonia, in the presence of sodium oxide present process is superior to those using alkali and in the presence of ferric nitrate enneahy metal acetylides prepared from the alkali metal drate, passing acetylene gas into the solution un and the acetylene in that hydrogenation loSSes are til the gray color thereof turns to black, adding avoided. ethylhexanal at about -40° C., and isolating the As has already been pointed out, the Sodium heptylethynylcarbinol. acetylide and the sodamide used in the present 4. Process of preparing heptenylethynylcarbi process are more reactive and more soluble in nol which comprises reacting sodium with an ex liquid ammonia, when they are not isolated from cess of liquid ammonia in the presence of sodium the reaction mixtures in which they are prepared. Oxide and in the presence of ferric nitrate ennea 10 O To this fact is attributed in part the Superiority hydrate, passing acetylene gas into the solution until the gray color thereof turns to black, adding of the process of the present invention Over proc ethylhexenal at about -40° C., and isolating the esses disclosed in the art. The highly soluble heptenylethynylcarbinol. and reactive sodium acetylide described herein 5. Process of preparing ethynylcarbinols hav 15 15 cannot be obtained by reacting acetylene with ing a hydrogen and a seven carbon atom aliphatic Sodamide of the commercial variety. Ordinary residue on the carbinol carbon which comprises Sodium acetylide is not satisfactory for the pur reacting an alkali metal with an excess of liquid poses of this invention since it is neither suffi ammonia in the presence of an alkali metal oxide ciently soluble in liquid ammonia nor sufficiently and in the presence of an ammonia-soluble hy 20 20 reactive to produce the high yields which are drated Salt of a ferrous metal, passing acetylene characteristic of the present proceSS. gas in excess into the solution thus prepared, then In the specification and claims by 'ammonia' adding at about -40° C. an aliphatic aldehyde is meant the compound NH3 and not the solution containing eight carbon atoms and isolating the thereof in water which is ammonium hydroxide. ethynylcarbinol thus produced. 25 The term “alkyl' is used in the sense of a sat 6. Process of preparing ethynylcarbinols hav urated aliphatic hydrocarbon radical. The term ing at least one hydrogen on the carbinol carbon “ferrous metal' is used in the Sense of a metal which comprises reacting an alkali metal with an of the class consisting of iron, cobalt and nickel. excess of liquid ammonia in the presence of an The above description and examples are in alkali metal oxide and in the presence of an 30 30 tended to be illustrative only. Any modification ammonia-soluble hydrated salt of a ferrous met of or variation therefrom which conforms to the al, reacting acetylene with the alkali amide thus spirit of the invention is intended to be included prepared, reacting the alkali acetylide thus pre within the scope of the claims. pared with an aldehyde and isolating the pri I claim: mary or Secondary carbinol. - 1. Process of preparing methylethynylcarbinol 7. In the process of preparing ethynylcarbi which comprises reacting 46 parts of sodium with nols having at least one hydrogen on the carbinol an excess of liquid ammonia, in the presence of carbon, the step which consists in reacting an 1.3 parts of sodium oxide and in the presence of aldehyde with a liquid ammonia solution of an 0.3 part of ferric nitrate enneahydrate, passing 40. 40 acetylene gas into the ammonia solution of sod alkali metal acetylide of the formula MCsCH amide thus prepared at -50° C. to -40° C. until Wherein M is an alkali metal, said solution being the gray color thereof changes to black, adding that in which the alkali metal acetylide is formed. 88 parts of dry acetaldehyde to the sodium acet 8. Ethynylcarbinols of the formula R ylide thus obtained, and isolating the methyl N 45 45 ethynylcarbinol by evaporating the ammonia, CE-OB dissolving the residue in water, acidifying and Steam distilling the aqueous acid solution, and HCSC Salting out the product from the steam distillate, wherein R is a seven carbon aliphatic hydrocar 2. Process of preparing methylethynylcarbinol bon radical. 50 50 Which comprises reacting sodium with an excess 9. Heptylethynylcarbinol of the formula of liquid ammonia in the presence of sodium oxide CH3-CH2-CH2-CH and in the presence of ferric nitrate enneahy CH(C2H5)-CHOH. CsCH. drate, passing acetylene gas into the solution un 10. Heptenylethynylcarbinol of the formula til the gray color thereof turns to black, adding 55 55 acetaldehyde at about -40° C., and isolating the CH3-CH2-CH2-CH=C(C2H5)-- - nethylethynylcarbino. CHOH-CsCH, 3. Process of preparing heptylethynylcarbinol which comprises reacting sodium with an excess OSCAR, ROBERT KREIMEIER,

CERTIFICATE OF CORRECTION. Patent No. 2,106.8.l. r January 25, 1958. OSCAR ROBERT KREMEIER, It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2 second column, line 60, for the words "An aldehyde" read Any aldehyde; 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 3d day of May, A. D. 1958.

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