United States Patent (19. 11 3,876,708 Speh et al. (45) Apr. 8, 1975

54 ORTHOCARBONIC ACID 56) References Cited 75) Inventors: Peter Speh, Esslingen-Hegensberg; OTHER PUBLICATIONS Willi Kantlehner, Aalen, both of Chem. Abs., 7th Col. Index (1962-1966), Subj. Germany A-Amm., pg. 380 S. 73) Assignee: Fluka AG Chemische Fabrik, Buchs Chiang et al., Chem. Abs., Vol. 61 (1964), 13169. S.G., Switzerland Post, Chemistry of Aliphatic Orthoesters (1943) page 22 Filed: Oct. 30, 1972 20. 21 Appl. No.: 301,784 Primary Examiner-Bernard Helfin Attorney, Agent, or Firm-Wallenstein, Spangenberg, 30 Foreign Application Priority Data Hattis & Strampel Nov. 15, 1971 Switzerland...... 16537.17 57 ABSTRACT 52 U.S. Cl...... 260/611 R; 260/615A; 260/63R; Orthocarbonic acid esters are prepared from 1 mole 260/576 of trichloro acetonitrile and 4 moles of an alkali metal (51 int. Cl...... C07 c 43/32 or alkaline earth metal salt of which contain 58 Field of Search...... 260/615 A, 61 1 R, 613, at least one o-hydrogen. 260/576 20 Claims, No Drawings 3,876,708 2 ORTHOCARBONCACD ESTERS broad application, furnishes the desired final products The present invention relates to a new method for the in good yields and is easy to carry out. production of orthocarbonic acid esters of the general The method comprises reacting an alkali metal or an formula alkaline earth metal salt of an of the general C(OR), 5 formula R-OH I wherein R represents a saturated hydrocarbon residue, which may be substituted and wherein the atom O in which R has the above indicated significance, with bound to the oxygen atom contains at least one hydro trichloro acetonitrile. gen atom. It is expedient to effect the conversion of such an al The saturated hydrocarbon residue which may be coholate with tricholoro acetonitrile in an organic sol substituted, identified in the above formula I as R may vent which is inert under the conditions of the reaction. be a straight chain or a branched alkyl residue, specifi 5 Dipolar, aprotic solvents, like, for example, dimethyl cally, it may be one containing up to seven, preferably formamide, dimethylsulfoxide, acetonitrile, tetrahydro one to four, carbon atoms, such as methyl, ethyl, pro furan, dimethoxyethane, sulfolane, hexamethylphos pyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, neo phoric acid triamide and the like are solvents appropri pentyl and the like. Cycloalkyl residues, particularly ate for this purpose. those containing three to eight carbon atoms and cyclo However, the use of the alcohol of formula II as a so alkyl alkyl residues, especially those containing four to vent, which corresponds to the alcoholate used as the 10 carbon atoms, may be represented by the symbol R. reaction component, is advantageous. While pressure Cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cy is not a critical factor, for reasons of expediency it is clopropylmethyl, cyclohexylethyl and the like are ex preferable to operate at normal pressure. Neither is the amples of such residues. Residues in which the carbon 25 temperature a critical factor, but it is preferred to carry atom bound to the oxygen atom shows no hydrogen out the reaction at elevated temperature, which is of atom, i.e., tertiary residues, such as tertiary butyl, how particular preference at the reflux temperature of the ever, are excluded according to the definition furnished reaction mixture. Sodium and potassium are the pre initially. One or several of the hydrogen atoms in the 30 ferred cations in the alcoholates used as reaction com residues identified by the symbol R may be replaced by ponents. a substituent. Examples for such substituents are alk The alcoholates are prepared according to known oxy groups, such as methoxy, ethoxy and the like; aryl methods from the corresponding alcohols of formula II oxy groups such as phenyloxy and the like; amino which in turn are known compounds or can be pre groups disubstituted by alkyl and/or aryl such as di 35 pared in analogy to methods used in the preparation of methylamino, diethylamino, N-methylanilino and the known alcohols. like. The end products of the method according to the in The esters of formula I form part of a known class of vention, that is, the orthocarbonic acid esters of for compounds. However, within the scope of the present mula I, are valuable and multilaterally applicable inter invention, the following compounds have been pro 40 mediate products for the synthesis of the most diverse duced for the first time: classes of compounds. For example, orthocarboxylic Orthocarbonic acid tetra-isopropyl acid esters and ketals, respectively, can be produced Orthocarbonic acid tetra-neopentyl ester from one mole of an orthocarbonic acid ester of for Orthocarbonic acid tetra-cyclohexyl ester mula by conversion with one or two moles respec These heretofore unknown compounds also are the 45 tively, of a Grignard compound. OH-acid compounds, subject of the present invention. They have chemical like phenols, carboxylic acids and the like can be ether properties which are considerably different from those ified or esterified, respectively, by conversion with es of previously known orthocarbonic acid esters. Thus, ters of formula I. Furthermore, orthocarbonic acid es for example, the orthocarbonic acid tetra-isopropyl ters of formula I show synthetically usable reactions ester is markedly more stable towards hydrolysis than 50 with enol ethers, styrenes, ammonia, amines, sulfona e.g. the corresponding tetra-ethyl ester. The said novel mides, certain organic phosphorous compounds etc. compounds are particularly useful, e.g. as alkylating Moreover, they can be converted into other orthocar agents because they can be used for introducing resi bonic esters by reesterification with appropriate alco dues which cannot be easily introduced by known hol compounds, for example, also into such kinds methods, e.g. by means of oxonium salts. 55 which are not directly obtainable according to the The literature describes some methods for the pro method of the invention. duction of orthocarbonic acid esters, but all of them The following example illustrates the method accord have some disadvantages or others. For example, none ing to the invention. All temperatures are indicated in of these methods permits the introduction of residues degrees centigrade (°C). branched in the alpha position, such as isopropyl. 60 Moreover, according to some of these methods only EXAMPLE quite specific esters can be produced. Other disadvan 1 mole of freshly distilled is tages of these methods of the prior art are starting ma added dropwise to 4 moles alcoholate in about 700 ml terials with difficult accessibility, difficulties of operat of the corresponding alcohol under agitation and exclu ing on a large scale and the like. 65 sion of moisture at a temperature ranging from about In contrast to these methods described in literature, 30 to 80. Upon completion of the addition the reac the method according to the invention allows for a very tion mixture is heated to reflux for 3 hours, the precipi 3,876,708 3 4 tated salt is filtered off and the filtrate is fractionated l mole of trichloro acetonitrile at an elevated tem via a Raschig column 40 cm high. perature. According to the foregoing procedure, the following 5. A method according to claim 4, wherein the con compounds of formula I were produced. version is carried out in an organic solvent inert under Orthocarbonic acid tetramethyl ester, boiling point the reaction conditions, 1139; 10 1.3850 6. A method according to claim 5, wherein dimethyl Orthocarbonic acid tetraethyl ester, boiling point formamide, dimethylsulfoxide, acetonitrile, tetrahydro 159° furan, dimethoxyethane, sulfolane or hexamethylphos Orthocarbonic acid tetra-n-propyl ester, boiling phoric acid triamide are used as solvents. point 90°-93°/10 Torr, n° 1.3998 10 7. A method according to claim 4, wherein the con Orthocarbonic acid tetraisopropyl ester, boiling version is carried out in the alcohol of formula II corre point 70/10 Torr; n° 1.3933 sponding to the alcoholate used as a reaction compo Orthocarbonic acid tetra-n-butyl ester, boiling point nent in claim 1. 136°/10 Torr; 120 1.4206 8. A method according to claim 4, wherein sodium or Orthocarbonic acid tetraisobutyl ester, boiling point 5 61-62/108 Torr; in 14140 potassium is the cation of the alcoholate used as a reac Orthocarbonic acid tetraisopentyl ester, boiling point tion component. 81-82°/ 10 Torr 9. A method according to claim 4, wherein R repre Orthocarbonic acid tetraneopentyl ester, melting sents an unsubstituted saturated hydrocarbon residue. point 78°-79° 20 10. A method according to claim 9, wherein R repre Orthocarbonic acid tetracyclohexyl ester, melting sents methyl. point 101-103° 11. A method according to claim 9, wherein R repre We claim: sents ethyl. 1. Orthocarbonic acid-tetraisopropyl ester. 12. A method according to claim 9, wherein R repre 2. Orthocarbonic acid-tetraneopentyl ester. 25 sents n-propyl. 3. Orthocarbonic acid-tetracyclohexyl ester. 13. A method according to claim 9, wherein R repre 4. A method for the production of orthocarbonic sents iso-propyl. 14. A method according to claim 9, wherein R repre acid esters of the general formula sents n-butyl. C(OR) 15. A method according to claim 9 wherein R repre 30 sents iso-butyl. 16. A method according to claim 9, wherein R repre wherein R represents a saturated hydrocarbon resi sents iso-pentyl. due, which may be substituted and wherein the car 17. A method according to claim 9, wherein R repre bon atom bound to the oxygen atom contains at 35 sents neo-pentyl. least 1 hydrogen atom 18. A method according to claim 9, wherein R repre which comprises reacting 4 moles of an alkali metal or sents cyclohexyl. an alkaline earth metal salt of an alcohol of the general 19. A method according to claim 4, wherein the con formula version is carried out under reflux temperature condi 40 tions. R-OH 20. A method according to claim 5, wherein the con version is carried out under reflux temperature condi tions. in which R has the above indicated significance with ck k -k sk. k. 45

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