2-Methyleneglutaronitrile

File:2-Methylenglutaronitril Struktur.svg 200px 2-Methylidenepentanedinitrile 2,4-dicyano-1-butene2-Methylenepentanedinitrile 1572-52-7 74080 216-391-8 0Y85F7Y2B8 3182918 66697 1S/C6H6N2/c1-6(5-8)3-2-4-7/h1-3H2 NGCJVMZXRCLPRQ-UHFFFAOYSA-N C=C(CCC#N)C#N C6H6N2 106.13 g·mol−1 clear, colourlesshttp://www.tcichemicals.com/eshop/en/us/commodity/M0222/ 2-Methyleneglutaronitrile 1572-52-7 TCI America www.tcichemicals.com en 2018-01-14 2018-01-15 https://web.archive.org/web/20180115001550/http://www.tcichemicals.com/eshop/en/us/commodity/M0222/ dead liquid 0.976 g·cm−3 (25 °C)Aldrich 125547 2-Methylenglutaronitril 25. Juni 2017 Warning 07 302 312 332 261 264 270 271 280 301+312 302+352 304+312 304+340 312 322 330 363 501 2-Methylene glutaronitrile is a dimerization product of acrylonitrile and a starting material for di- and triamines, for the biocide 2-bromo-2-(bromomethyl)pentanedinitrile and for heterocycles, such as 3-cyanopyridine. Preparation 2-Methylene glutaronitrile is a side-product in the production of hexanedinitrile which is used (after hydrogenation to 1,6-diaminohexane) as a key component for engineering polymers such as the polyamides (PA 66) or polyurethanes. Hexanedinitrile can be industrially produced by electrochemical hydrodimerisation or by catalytic dimerization of acrylonitrile. A catalytic tail-tail dimerization of two acrylonitrile molecules forms hexanedinitrile: 400px|center|Hydrodimerisierung von Acrylnitril zu Adiponitril Also head-to-tail dimerization can occur in the process. In the presence of tricyclohexylphosphine (PCy3) a yield of up to 77% 2-methylene glutaronitrile can be obtained:L. Yu et al RSC Adv. Practical and scalable preparation of 2-methyleneglutaronitrile via an efficient and highly selective head-to-tail dimerization of acrylonitrile catalysed by low-loading of tricyclohexylphosphine 4 19122–19126 2014 37 10.1039/C4RA02810D 2014RSCAd...419122Y 400px|center|Dimerisierung von Acrylnitril zu 2-Methylenglutaronitril Metal halides (such as zinc chloride US 3733351 Production of 2-methylene-glutaronitrile 1973-05-15 1969-04-25 Y. Watanabe, M. Takeda Mitsubishi Petrochemical Co. US 4422981 Process for production of 2-methyleneglutaronitrile 1983-12-27 1982-03-24 H. Omori, M. Takeda, K. Fujita, M. Kataoka Mitsubishi Petrochemical Co. or aluminium chloride US 3956358 Dimerization method 1976-05-11 1974-12-30 O.T. Onsager Halcon International, Inc.) are used with tertiary amines (such as triethylamine) as catalysts for the dimerization. Crude yields of up to 84% are achieved. Often, significant amounts of product are lost during the work-up (e. g. extraction and distillation) because of the tendency to polymerization of 2-methylene glutaronitrile. In addition to the linear dimerization products 1,4-dicyano-2-butene and 1,4-dicyano-3-butene (obtained as cis-trans isomer mixtures) usually also other oligomers (and polymers) of acrylonitrile are formed. During the electrochemical hydrooligomerization of acrylonitrile, these are trimers, such as 1,3,6- and 1,3,5-tricyanohexane or tetramers, such as 1,3,6,8- and 1,3,5,8-tetracyanooctane.M.M. Baizer J.D. Anderson J. Org. Chem. Electrolytic reductive coupling. VII. A new class of acrylonitrile oligomers 30 5 1351–1356 1965 10.1021/jo01016a003 The reaction of acrylonitrile with tributylphosphine affords 2-methyleneglutaronitrile in a modest yield of about 10% after fractional distillation.M.M. Baizer J.D. Anderson J. Org. Chem. Electrolytic reductive coupling. VIII. Utilization and a new preparation of α-methyleneglutaronitrile 30 5 1357–1360 1965 10.1021/jo01016a004 The DABCO-catalyzed acrylonitrile dimerization of 2,4-dicyano-1-butene after 10 days at room temperature is with 40% yield similarly inefficient.D. Basavaiah V.V.L. Gowriswari T.K. Barathi Tetrahedron Lett. DABCO catalyzed dimerization of α, β-unsaturated ketones and nitriles 28 39 4591–4592 1987 10.1016/S0040-4039(00)96573-0 Use The earlier patent literature describes processes for the isomerization of 2-methylene glutaronitrile to 1,4-dicyanobutenes as hexanedinitrile precursors, which became obsolete with the optimization of the electrochemical hydrodimerization of acrylonitrile to hexanedinitrile. US 3795694 Preparation of cyano compounds 1974-03-05 1972-10-16 O.T. Onsager Halcon International, Inc. The electrochemical hydrodimerization of 2-methylene glutaronitrile produces 1,3,6,8-tetracyanooctane. 600px|center|Hydrodimerisierung von 2-Methylenglutaronitril In the hydrogenation of 2-methylene glutaronitrile in the presence of palladium on carbon, hydrogen is attached to the double bond and 2-methylglutaronitrile is obtained in virtually quantitative yield. US 3350439 Process for preparing aminoalkanenitriles 1967-10-31 1965-06-01 J. Feldman, M. Thomas National Destillers and Chemical Corp. The hydrogenation of the nitrile groups requires more severe conditions and the presence of ammonia or amines to suppress the formation of secondary amines. This second hydrogenation step is carried out with Raney-cobalt as the hydrogenation catalyst to give 2-methyl-1,5-pentanediamine in 80% yield. US 3408397 Methyl pentamethylene diamine process 1967-10-31 1965-06-01 J. Feldman, M. Thomas National Destillers and Chemical Corp. 550px|center|Hydrierung von 2-Methylenglutaronitril zu 2-Methyl-1,5-pentandiamin Hydrogenation of 2-methylene glutaronitrile in the presence of ammonia with manganese-containing sodium oxide-doped cobalt catalyst (at 80 to 100 °C and pressures of 200 atm in a tubular reactor) leads to the addition of ammonia to the double bond and directly converts the compound to 2-aminomethyl-1,5-pentanediamine with yields of 66%. EP 1028104 Verfahren zur Herstellung von 2-Aminomethyl-1,5-pentandiamin 2000-08-16 2000-01-27 K. Fischer, F. Richter, A. Bazanov, A. Timofeev, N. Zubritskaya, G. Smirnova Bayer AG 450px|center|Bildung von 2-Aminomethyl-1,5-pentandiamin The branched triamine can be used in epoxides and polyurethanes. 2-Methylenglutaronitrile reacts with methanamide upon catalysis with 4-(dimethylamino)-pyridine (DMAP) at 60 °C in 47% yield to give 1-(N-methanoylamino)-2,4-dicyanobutane, from which α- aminomethylglutaric acid is formed by subsequent hydrolysis. EP 0336185 1-(N-Formylamino)-2,4-dicyanobutan und ein Verfahren zu dessen Herstellung 1989-10-11 1989-03-18 H.-J. Scholl Bayer AG 500px|center|Reaktion von 2-Methylenglutaronitril mit Formamid zu 1-(N-Formylamino)-2,4-dicyanobutan Heating 2-methyleneglutaronitrile with an alkaline ion exchanger, pyridine and water to 150 °C in an autoclave yields the lactam 5-cyano-2-piperidone in 80% yield. US 3666766 Selective hydrolysis and cyclization of unsaturated nitriles 1972-05-30 1967-12-27 J.B. Pedigo, J. Feldman, I.A. Kereszies National Distillers and Chemical Corp. 350px|center|Lactambildung zum 5-Cyano-2-piperidon 2-Methylene glutaronitrile can be polymerized to various homo- and copolymers via anionic polymerization with sodium cyanide, sodium in liquid ammonia or with butyllithium. However, the polymers are formed only in low yields and show unsatisfactory properties such as intrinsic viscosities and poor mechanical properties. US 3451977 Process for polymerizing 2-methylene glutaronitrile 1969-06-24 1964-07-27 J.M. Hoyt, K. Koch National Distillers and Chemical Corp. The main use of 2-methyleneglutaronitrile is as starting material for the broad-spectrum biocide 2-bromo-2-(bromomethyl)pentanedinitrile (methyldibromo-glutaronitrile), US 3644380 Preparation of 3-cyanopyridine 1972-02-22 1969-11-24 R. Harmetz, R.J. Tull Merck & Co., Inc. which is formed in virtually quantitative yield by the addition of bromine to the double bond. US 3929858 Method for preparing 2-bromo-2-bromomethyl-glutaronitrile 1975-12-30 1974-12-03 R.D. Swigert Merck & Co., Inc. 400px|center|Bromierung von 2-Methylenglutaronitril From the chlorine-analogous 2-chloro-2-(chloromethyl)pentenenitrile, 3-cyanopyridine is obtained by heating to 150 °C with tin(IV)chloride. 350px|center|Bildung von 3-Cyanpyridin aus 2-Methylenglutaronitril References Category:Vinylidene compounds Category:Nitriles