Synthesis of cyanoacrylate esters by oxidation of aromatic selenyl cyanopropionates

lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll US005504252A United States Patent [19] [11] Patent Number: Klemarczyk [45] Date of Patent: 5,504,252 Apr. 2, 1996 [54] SYNTHESIS OF CYANOACRYLATE ESTERS BY OXIDATION OF AROMATIC SELENYL CYANOPROPIONATES hold pub. Payne, et al., I. Org. Chem, 26, 1961, pp. 651—659. Linn, et a1., “Organic Synthesis,” Coll. vol. 5, 1973, pp. [75] Inventor: Philip Klemarczyk, Collinsville, Conn. Hudlicky, “Oxidations in Organic Chemistry,” ACS Mona graph 186, 1990, pp. 230-231. Oakwood, et 21., “Organic Synthesis”, Coll. vol. 3, 1955, pp. 1007—1011. [73] Assignee: Loctite Corporation, Hartford, Conn. 114—115. [21] Appl. No.: 435,983 [22] Filed: May 5, 1995 Corson, et 21., “Organic Synthesis”, Coll. vol. 1, 1932, pp. [51] Attorney, Agent, or Firm—Vidas, Arrett, & Steinkraus 336-340. Int. Cl.6 ................................................. .. C07C 253/30 [52] 558/379; 558/443 [58] Field of Search .................................... .. 558/379, 443 [56] U.S. PATENT DOCUMENTS 2,467,926 12/1945 Long ..................................... .. 260/464 4/1949 Ardis .. . .. ... .. . . . .. 2,721,858 10/1955 Joyner et al. 3,254,111 5/1966 3,355,482 11/1967 Hawkins et a1. ... ..... Coover, Jr. et a1. 3,654,340 4/1972 .... 8/1969 Ray et al. ......... .. Banitt .... .. 4,012,402 3/1977 Buck ......... .. 4,153,641 5/1979 Deichert et a1. 5,140,084 8/1992 Mikuni et al. .... .. 5,140,840 8/1992 5,359,101 Miceli 260/465.4 260/465.4 3,463,804 [57] ABSTRACT A method of preparing an ot-cyanoacrylate ester of a desired alcohol includes the steps of References Cited 2,391,251 Primary Examiner-Joseph Paul Brust ... .. .... ... . . . . .. 260/465.4 . . . . . . .. 260/464 260/465 . 260/465.4 526/298 X 260/827 526/279 . . . . . . .. 63/12 10/1994 Woods et al. ........................... .. 556/52 OTHER PUBLICATIONS Skeist, “Handbook of Adhesines”, 3rd Ed,. 1990, pp. 466467, Reinhold pub. Schumb, et al., “Hydrogen Peroxide”, 1955, p. 410; Rein preparing a compound which is an ot-selenoaryl-ot-cyano propionate ester of the desired alcohol, oxidizing said oeselenoaryl-ot-cyanopropionate ester to the corresponding selenoxide, eliminating arylselenic acid from the selenoxide to pro duce said ot-cyanoacrylate ester, and separating said ot-cyanoacrylate' ester from the selenic acid. At temperatures of about 0° C. or higher, the elimination step occurs concurrently with the oxidizing step using a peroxide or ozone oxidizing agent. The desired cyanoacry late ester is obtained in good yield and very high purity. The method can be used to prepare di?icult to synthesize plural functional cyanoacrylate monomers and mono- cyanoacry late monomers regardless of alcohol chain length. 24 Claims, No Drawings 5,504,252 1 2 SYNTHESIS OF CYANOACRYLATE ESTERS BY OXIDATION OF AROMATIC SELENYL having plural cyanoacrylate functionality in reasonable yield CYANOPROPIONATES In Reich, et al, JACS, 97, 5434-47 (1975) and Bucheister, et al, Organometallics, 1, 1679-84 (1982), it is reported that BACKGROUND OF THE INVENTION certain otB-unsaturated methyl or ethyl esters were prepared by oxidation/elimination reactions performed on corre and with less di?‘iculty than that of U.S. Pat. No. 4,012,402. The most common method for the production of sponding methyl or ethyl ot-selenoarylpropionate esters. However it has not been previously proposed or suggested cyanoacrylate monomers involves the base catalyzed Kno evenagel condensation of cyanoacetate with formaldehyde, followed by acid catalyzed therrnolysis of the intermediate to try to use such procedure to prepare ot-cyanoacrylate esters, nor has it been proposed or suggested to try to prepare polymer. This method is exempli?ed in many references, for esters of C8 or higher alcohols or plural ester compounds by instance U.S. Pat. Nos, 2,721,858; 3,254,111; 3,355,482; 3,654,340; 5,140,084 and 5,359,101. This method is e?ec tive and inexpensive in producing low molecular weight monomers, but as the size of the cyanoacrylate ester increases the method becomes more di?icult and yields preparation and oxidation/elimination of ot-selenoaryl-ot cyanopropionate esters. 15 SUMMARY OF THE INVENTION diminish substantially. Cyanoacrylate esters of monofunc tional C8 or higher aliphatic alcohols cannot be produced in The present invention is directed to a novel method for preparing cyanoacrylate monomers which can be used to commercially practical yields by this method. There are several other synthetic methods known for 20 prepare di?icult to synthesize higher molecular weight producing cyanoacrylates including: cyanoacrylate monomers and plural functional cyanoacry Diels-Alder protection/deprotection as exempli?ed by U.S. Pat. No. 3,463,804 and 4,012,402; late monomers as well as more conventional monofunctional cyanoacrylate monomers in high yield and by a relatively simple procedure. transesteri?cation of cyanoacrylate monomers with alco hols as reported in WPI 80-82239C/46, abstracting (SU 726086 (1980)); 25 direct esteri?cation of cyanoacrylic acid with alcohols as reported in DE 34 15 181 (1984); thermal decomposition of alkyl 2-cyano-3-alkoxypropi onates and the 3-acyloxy analogs, reported in U.S. Pat. No. 2,467,926; and pyrolysis of the cyanohydrin acetates of pyruvic acid esters, reported in U.S. Pat. No. 2,391,251. Monomers having a plurality of cyanoacrylate groups per molecule are particularly desirable because they can give 35 crosslinked products on polymerization, alone or in combi nation with conventional monofunctional cyanoacrylate monomers. Crosslinked polymers give improved properties such as solvent resistance. The Diels-Alder protection! 40 The invention in one aspect is a method of preparing an tat-cyanoacrylate ester of a desired alcohol, the method comprising the steps of preparing a compound which is an oz-selenoaryl-ot-cyano propionate ester of said alcohol, oxidizing said ot-selenoaryl-ot-cyanopropionate ester to the corresponding selenoxide, eliminating arylselenic acid from said selenoxide to pro duce said ot-cyanoacrylate ester, and separating said ot-cyanoacrylate ester from said arylse lenic acid. At temperatures of about 0° C. or higher, the elimination step occurs concurrently with the oxidizing step using a peroxide or ozone oxidizing agent. The desired cyanoacry late ester is obtained in good yield and very high purity. deprotection disclosed in U.S. Pat. No. 4,012,402 has been used to prepare various bis-cyanoacrylate monomers. How ever, the method is cumbersome and not suited to commer cial production. Kadykov, et. al., “Synthesis and Properties of Siloxane DETAHJED DESCRIPTION OF THE PREFERRED EMBODIMENTS 45 Cyanoacrylate Adhesives, ” Plast. massy, 1984, No. 10, hydroxypropyldimethylsiloxane" by reaction of one mole diepoxydimethylsiloxane and two moles ot~cyanoacrylic acid in the presence of 0.03 moles tertiary amine catalyst and 0.05 mole hydroquinone monomethyl ether. The reaction is reported to be exothermic and to produce the bis-ester of the formula: In the inventive method as described above, the ot-sele noaryl-cx-cyanopropionate ester is suitably prepared by pp.8—9, reports an alleged syntheses of “diacryl-ot-cyano-B treating a corresponding (ll-cyanopropionate ester with a base of su?icient strength to abstract an ot-H atom from the 50 cyanopropionate ester and adding an arylselenylhalide of the formula where Ar is an aryl group and X is Cl , Br or I. CN on ?H3 on CN 55 481/ O\)\/O_?l~ \/l\/o% 0 CH3 0 However, the reaction conditions employed make it unlikely that such a product could actually be isolated and the analytical data reported in this reference on the product 60 The ot-cyanopropionate ester of the desired alcohol can be prepared by known means. In general any means suitable for preparing ot-cyanoacetate esters can be readily modi?ed by known methods to prepare corresponding ot-cyanopropro pionate esters. Such methods include acid catalyzed direct esteri?cation of cyanopropionic acid with an alcohol, optionally in the presence of 2-halopyridinium salts; base catalyzed alkylation reactions of cyanopropionic acid with which was isolated is believed to con?rm that the product alkyl halides; acid or base catalyzed transesteri?cation reac was not the bis-cyanoacrylate. tions; nucleophilic substitution reactions where chloropro There therefore exists a need for further alternative meth 65 pionates are treated with alkali cyanides in a direct cyanation ods for cyanoacrylate ester production and in particular reaction; and direct acylation reactions of alcohols with methods which can be used for production of monomers cyanopropionyl chloride. 5,504,252 3 4 The invention is particularly advantageous for preparing cyanoacrylate esters of C8 or higher alcohols, including aliphatic and aromatic alcohols, for instance C8-C22 hydro carbon alcohols and alkoxylated hydrocarbon alcohols such matic selenic acid is insoluble in common organic solvents as ethoxylated nonyl phenol and similar surfactant com pounds. The inventive method can also be used to prepare and so is readily separated from the cyanoacrylate. In the case of the two-phase reaction described above separation of plural functional cyanoacrylate compounds, i.e. from cyano propionate esters of plural hydroxy functional compounds. the cyanoacrylate ester is accomplished simply by separa— tion of the organic layer. Such plural hydroxy functional compounds can be simple diols, triols or tetraols such as ethylene glycol, propylene recycled by reduction to the corresponding diaryldiselenide glycol, 1,3-propane diol, l,4,-butanediol, trimethylolpro in accordance with the known method described in the Reich pane, 1,6-hexanediol, pentaerythritol, diethylene glycol, tet et.al. reference described above, followed by conversion of the diaryldiselenide to a selenoaryl halide by reaction with raethylene glycol and the like or oligomeric prepolymer compounds such as polyethylene glycol, hydroxy terminated polybutadiene, hydroxy terminated polyesters and the like. The arylselenyl halide is suitably prepared from a diaryl At temperatures above about 0° C. elimination of the aryl selenic acid occurs spontaneously without added reactant or catalyst to yield the desired cyanoacrylate ester. The aro The arylselenic acid byproduct of the reaction can be chlorine, bromine or iodine. 15 EXAMPLES diselenide such as diphenyldiselenide by addition of the molecular halogen X2. Suitable Ar groups are substituted or unsubstituted phenyl groups. Suitable phenyl group substi~ Ethyl cyanopropionate was obtained from TCI America and was used without further puri?cation. Diphenyl dis tutions include halo, alkyl, alkoxy and haloalkyl. Speci?c examples of substitutions include methyl, ethyl, phenyl, chloro, ?uoro, tri?uoromethyl, methoxy and ethoxy. Prefer recrystallized from ethanol prior to use. THF was distilled ‘ ably X is Br. Examples of bases of su?icient strength to abstract an ot-H atom from the cyanopropionate ester include the alkali elenide was purchased from Aldrich or Janssen and was from sodium/benzophenone immediately before use. Sodium hydride was purchased from Aldrich as a 95% powder and was stored in a desiccator. Reaction glassware was oven dried before use. All glass 25 ware was immersed overnight in 0.5M H2804, rinsed with deionized water and oven dried. All transfers of dried solvents were performed with a syringe. hydride bases NaH, KH, LiH, and alkylalkalides, such as n-butyllithium. Alkali hydride bases are preferred as the byproduct H2 is removed continuously as a gas driving the reaction to completion. Alkali-amide bases, such as lithium diisopropyl amide, and alkoxide bases, such as sodium methoxide, are generally undesirable as they introduce addi~ Proton NMR spectra were obtained on a Varian Gemini 30 300 MHZ NMR spectrometer. IR analyses were done on an ATI Mattson Genesis Series FI‘IR. tional amine or alcohol by-products which may be more di?icult to completely remove during work-up of the ot-se lenoaryl-ot-cyanopropionate ester. Isolation and puri?cation of the ot~selenoaryl-or-cyano~ propionate ester can usually be readily accomplished by EXAMPLE 1 PREPARATION OF 2-OCTYL CYANOACRYLATE 35 dissolution in a suitable solvent such as ether (diethyl ether) and aqueous extraction of the solution followed by evapo ration of the solvent. In general further puri?cation is The method of this example may be represented by the following equation: unnecessary but in some cases it can be bene?cial. Further 40 puri?cation can for instance crystallization, suitably from a cooled ether solution. The cyanoacrylate ester is formed by an oxidation/elimi nation reaction. The mechanism is believed to involve two steps which occur concurrently at ambient temperature but 45 which can be separated into two stages if the oxidation is carried out at temperatures no higher than about 0° C. Reaction at temperatures above 0° C. is preferred as there is no bene?t to isolating the intermediate selenoxide product of the oxidation reaction. Temperatures is excess of about 40° C. are also preferably avoided because the cyanoacrylate product may polymerize at elevated temperatures and because the reaction is highly exothermic and can become di?icult to control at higher temperatures. Suitable oxidizing agents are peroxide compounds and ozone. Hydrogen peroxide is generally preferred as it is inexpensive, effective and relatively easy to handle. Other oxidizing agents which may be particularly useful in some circumstances include m-chloroperbenzoic acid and sodium iodate. 55 CH3 CH3 \l Y CH2 1 CH3 2 PHENYLSELENIUM BROMIDE To a 3-neck 250 ml ?ask, equipped with a nitrogen inlet, magnetic stirrer, and rubber septum, was added diphenyl diselenide (20.9 g, 67 mmol) and THE‘ (100 ml) under nitrogen. Bromine (9.8 g, 61 mmol) was added by syringe. The solution was stirred for 5 minutes. 2-Octyl Cyanopropionate phenylselenide (1) To a 4-neck 500 ml ?ask, equipped with a condenser, 60 mechanical stirrer, thermometer, and nitrogen inlet, was added sodium hydride (3.9 g, 153 mmol) and THE (250 m1) The oxidation reaction is suitably carried out in a two under nitrogen. 2-octyl-2-cyanopropionate (20 g, 115 mmol) phase reaction in which the ot-selenoaryl-ot-cyanopropionate was added over 10 min. and the reaction mixture was stirred for 1 hour at room temperature. A solution of phenylsele~ ester is dissolved in a hydrophobic solvent such as methyl ene chloride, and the hydrogen peroxide is added as a solution in water, the two phases being vigorously agitated to effect reaction between the reactants in the respective phases. nium bromide, prepared by the above method, was added by 65 syringe. The reaction mixture was stirred for 1 hour and added to 250 ml each of ether and sat. aq. NaHCO3. The organic layer was washed twice with 250 ml of H20 and 5,504,252 5 6 once with 250 ml sat. aq. NaCl. The organic layer was the mixture was cooled in an ice bath. The bis-phenylse separated, dried (MgSO4) and ?ltered. Solvent was removed under reduced pressure. Yield=43.2 g (quant); NMR 5 lenide precipitated, was ?ltered, and washed with 5 ml of cold ether. Yield =6.5 g (29%), M.P.=1l3° C.; NMR 5 (CDCl3) 7.75 (d, 2H), 7.40 (rn, 3H), 4.85 (m, 2H), 1.80 (s, 3H), 0.8—1.70 (m, 16H); IR (neat) 2333, 1734, 1251 cm“. (CDCI3) 7.75 (d, 4H), 7.40 (m, 6H), 3.95 (m, 4H), 1.85 (s, 5 2-Octyl Cyanoacrylate (2) 6H), 1.40 (br s, 4H); IR (KBr) 2231, 1730, 1234 cm“. 1,4 Butanediol dicyanoacrylate (BDDCA) To a 500 ml ?ask, equipped with a condenser, mechanical stirrer, thermometer, and addition funnel, was added the stirrer, thermometer, and addition funnel, was added bis crude 2-octyl propionate phenylselenide (43.2 g, 115 mmol) and methylene chloride (300 ml). Hydrogen peroxide, 30% phenyselenide (6.5 g, 12 mmol) and methylene chloride (50 ml). Hydrogen peroxide, 30% (11.6 g, 102 mmol) was (47 g, 418 mmol) was dissolved in water (30 ml) and added to the reaction ?ask over 15 minutes. The reaction tempera ture was kept at 20°—30° C. with an ice bath. After the addition was complete, the reaction mixture was stirred for 1 hour at room temperature. The organic layer was separated dissolved in water (8 ml) and added slowly to the reaction To a 250 ml ?ask, equipped with a condenser, mechanical ?ask over 10 min. The temperature was maintained at 20°~30° C. with an ice bath. After the addition was com plete, the reaction mixture was stirred for 2 hours at room separated, dried (anhydr. silicic acid), and ?ltered. Solvent temperature. The organic layer was separated and washed with 50 ml of water The organic layer was separated, dried (anhydr. silicic acid) and ?ltered into a ?ask containing was removed under reduced pressure. The crude product was distilled under vacuum. Yield=14.4 g (60%), B.P.=95° densed under reduced pressure. Because of its reactivity, and washed once with 100 ml of H20. The organic layer was C./1.0 mm Hg; NMR 5 (CDCl3) 7.05 (s, 1H), 6.60 (s, 1H), 5.05 (m, 2H), 0.8-1.7 (m, 16H); IR (neat) 2236, 1732, 1649, 1287 cm_1; strong acid 51 ppm. 0.015 g of methanesulfonic acid. The solution was con 20 BDDCA was kept as a solution until just prior to use. Solvent was evaporated under vacuum in a desiccator from a plastic beaker, which had been immersed overnight in EXAMPLE 2 Preparation of 1,4 Butanediol dicyanoacrylate (BDDCA) 1,4 Butanediol dicyanopropionate 25 ,8 (CDCI3) 7.10 8(s, 2H), 6.65 (s, 2H), 4.35 (br t, 4H), 1.90 (br t, 4H); IR (KBr) 3.32 2237, 1729, 1615 cm‘l. TGA analysis showed that BDDCA homopolymer decomposed at To a 1000 ml 3-neck ?ask equipped with a Dean-Stark trap, condenser, thermometer, and nitrogen inlet, was added ethyl-2-cyanopropionate (50.8 g, 400 mmol), 1,4 butanediol (15.8 g, 175 mmol), p-toluenesulfonic acid (3 g, 16 mmol), 30 and toluene (500 ml) under nitrogen. The solution was heated to re?ux with stirring. Solvent was removed through the Dean-Stark trap and replaced with an equal volume of fresh toluene. After re?uxing for 8 hours, and removing 500 ml of solvent, the solution was cooled to room temperature. The solution was washed twice with 300 n11 of sat. aq. resistance on immersion in methylene ‘chloride overnight. EXAMPLES 3-7 of sat. aq. NaCl . The organic layer was separated, dried (MgSO4), and ?ltered. Solvent was removed under reduced When example 1 is repeated except that equivalent amounts of phenyl 2-cyanopropionate, 4-ethylphenyl cyano pressure. The crude product was puri?ed by vacuum distil propionate, n-octyl cyanopropionate, 4-nonylphenyl 2-cy lation. Yield:22.3 g (51%), B.P.=172° C. (0.6 mm/Hg); NMR 5(CDCl3) 4.25 (br t, 4H), 3.60 (q, 2H), 1.80 (br t, 4H), 1.60 (d, 6H); IR (neat) 2252, 1745 cm_1. anopropionate and stearyl 2-cyanopropionate are substituted in separate respective experimental runs for the starting 2-octyl 2-cyanopropionate used in example 1 and appropri ate equivalent weight adjustments are made throughout the PHENYLSELENIUM BROMIDE procedure, phenyl cyanoacrylate, 4-ethylphenyl cyanoacry~ late, n~octyl cyanoacrylate, 4-nonylphenyl cyanoacrylate and stearyl cyanoacrylate, respectively will be obtained in reasonable purity at the end of the procedure. 50 The solution was stirred for 5 min. EXAMPLES 8-12 1,4 Butanediol dicyanopropionate bis-phenylselenide To a 500 ml 4-neck ?ask, equipped with a condenser, mechanical stirrer, thermometer, rubber septum, and nitro gen inlet was added sodium hydride (2.7 g, 105 mmol) and about 65 ° C. higher than ethyl cyanoacrylate homopolymer. Polymerized mixtures of BDDCA at levels of 1, 5, l0 and 20 parts per hundred in ethyl cyanoacrylate, did not show any enhancement of thermal stability over the ethyl cyanoacry late homopolymer but did give signi?cant solvent swelling 35 NaHCO3, twice with 300 ml of H20, and once with 300 ml To a 3-neck 250 ml ?ask, equipped with a nitrogen inlet, magnetic stirrer, and rubber septum, was added diphenyl diselenide (17.2 g, 55 mmol) and THF (100 m1) under nitrogen. Bromine (7.2 g, 45 mmol) was added by syringe. 0.5M H2504, washed with deionized water and dried. The solid BDDCA is extremely reactive and was used immedi ately after evaporation of solvent, because it' polymerized ' within a few minutes in the solid state. M.P.=80° C.; NMR 55 When example 2 is repeated except that an equivalent amount of the 2-cyanopropionate esters of the following polyols are substituted in separate experimental runs for the anhydrous dimethyl formamide (200 ml) under nitrogen. starting 1,4-butane diol dicyanopropionate used in example Butanediol dicyanopropionate (10 g, 40 mmol) was added 2 and appropriate equivalent weight adjustments are made over 10 min. at room temperature, and the reaction mixture throughout the procedures, the corresponding plural was stirred for 2 hours. The previously prepared phenylse lenium bromide solution was added by syringe and the cyanoacrylate will be obtained in at the end of the procedure: 60 reaction mixture was stirred for 2.5 hours. The reaction mixture was added to 250 ml each of ether and sat. aq. NaHCO3. The organic layer was washed twice with 250 ml bis-hydroxy terminated mixed ortho and para phthalate/ of H20 and once with 250 ml of sat. aq. NaCl . The organic layer was separated, dried (MgSO4), and ?ltered. Solvent was removed under reduced pressure. Crude Yield=23.4 g (quant). To the crude product was added 10 ml of ether and bis~hydroxy terminated polyethylene glycol 400; bis-hydroxy terminated polyethylene glycol 1000; bis-hydroxy terminated polybutadiene; 65 diethylene glycol polyester; tris-hydroxy terminated adipate/ 1,4-butane diol-glycerine polyester (1 eq glycerol per molecule. 5,504,252 7 8 What is claimed is: 1. A method of preparing an ot-cyanoacrylate ester of a separating said ot~cyanoacrylate ester from the arylselenic acid. 13. A method as in claim 12 wherein said separation step comprises an extraction of said ot-cyanoacrylate ester into an preselected alcohol, the method comprising the steps of preparing a compound which is an ot-selenoaryl-ot-cyano propionate ester of said alcohol, oxidizing said ot-selenoaryl-ot-cyanopropionate ester to organic solvent. 14. A method as in claim 12 wherein said preselected alcohol is a C8 or higher mono or plural hydroxy functional the corresponding selenoxide, eliminating arylselenic acid from said selenoxide to pro- ' duce said ot-cyanoacrylate ester, and 10 separating said ot-cyanoacrylate ester from said arylse lenic acid. 2. A method as in claim 1 wherein said separation step comprises an extraction of said ot~cyanoacrylate ester into an compound. 15. A method as in claim 12 wherein said preselected alcohol is a compound having more than one hydroxy group per molecule and said ot-selenoaryl-ot-cyanopropionate ester is the ester corresponding to the esteri?cation product of each said hydroxy group with ot-cyanopropionic acid. 16. A method as in claim 15 wherein said preselected organic solvent. 3. A method as in claim 1 wherein said preselected alcohol is a C8 or higher mono or plural hydroxy functional com alcohol is a diol. pound. ot-cyanopropionate ester is prepared by reaction of a sele noaryl halide of the formula: 17. A method as in claim 12 wherein said ot-selenoaryl 4. A method as in claim 1 wherein said preselected alcohol is a compound having more than one hydroxy group per 20 molecule and said ot-selenoaryl-ot-cyanopropionate ester is the ester corresponding to the esteri?cation product of each where Ar is an aryl group and X is Cl, Br or I, with the ot-cyanopropionate ester of said alcohol. 18. A method as in claim 17 wherein X is Cl. is a diol. 25 19. A method as in claim 17 wherein X is Br. 6. A method as in claim 1 wherein said ot-selenoaryl-ot 20. A method as in claim 17 wherein Ar is phenyl which cyanopropionate ester is prepared by reaction of a selenoaryl is unsubstituted or substituted by one or more halo, alkyl, halide of the formula: haloalkyl or alkoxide groups. 21. A method as in claim 12 wherein, after said separation said hydroxy group with ot-cyanopropionic acid. 5. A method as in claim 4 wherein said preselected alcohol 30 where Ar is an aryl group and X is Cl, Br or I, with the ot-cyanopropionate ester of said alcohol. step, said arylselenic acid is recycled by reduction to the corresponding diaryldiselenide and conversion of said dia ryldiselenide to a selenoaryl halide by reaction with chlo 7. A method as in claim 6 wherein X is Cl. rine, bromine or iodine. 8. A method as in claim 6 wherein X is Br. 22. A method as in claim 12 wherein said oxidizing agent 9. A method as in claim 1 wherein, after said separation 35 is hydrogen peroxide and said reaction is e?'ected in an step, said arylselenic acid is recycled by reduction to the corresponding diaryldiselenide and conversion of said dia ryldiselenide to a selenoaryl halide by reaction with chlo rine, bromine or iodine. 10. A method as in claim 1 wherein said oxidizing step is agitated two phase reaction mixture, one phase being an 40 aqueous phase containing said hydrogen peroxide and the other phase being a non-aqueous phase containing said ot-selenoaryl-(x-cyanopropionate ester. 23. A method as in claim 6 wherein Ar is phenyl which is effected by reaction of said ot-selenoaryl-ot-cyauopropionate unsubstituted or substituted with one or more halo, alkyl, ester with an oxidizing agent selected from the group haloalkyl or alkoxide groups. 24. A method of preparing an ot-cyanoacrylate ester of a consisting of peroxide compounds and ozone. 11. A method as in claim 10 wherein said oxidizing agent is hydrogen peroxide and said reaction is effected in an agitated two phase reaction mixture, one phase being an preselected alcohol, the method comprising the steps of preparing a compound which is an ot-selenoaryliot-cyano propionate ester of said alcohol, the aryl group of said aqueous phase containing said hydrogen peroxide and the other phase being a non-aqueous phase containing said ot-selenoaryl-ot-cyanopropionate ester. ot~selenoaryl-(x-cyanopropionate ester being phenyl which is unsubstituted or substituted with one or more 12. A method of preparing an ot-cyanoacrylate ester of a 50 preselected alcohol, the method comprising the steps of preparing a compound which is an ot-selenoaryl-ot-cyano propionate ester of said alcohol, treating said ot-selenoaryl-ot-cyanopropionate ester with an oxidizing agent selected from the group consisting of peroxide compounds and ozone, and subjecting the reaction mixture at the time of or subsequent to said treatment to a temperature in excess of 0° C. to produce said ot-cyanoacrylate ester and arylselenic acid, and then 55 halo, alkyl, haloalkyl or alkoxide groups, treating said ot-selenoaryl-ot-cyano propionate ester with an oxidiz ing agent selected from the group consisting of perox ide compounds and ozone, and subjecting the reaction mixture at the time of or subsequent to said treatment to a temperature in excess of 0° C. to produce said ot-cyanoacrylate ester and arylselenic acid, and then separating said ot-cyanoacrylate ester from the arylselenic acid, said separation step comprising an extraction of said ot-cyanoacrylate ester into an organic solvent.