Aminomalononitriles

Aminomalononitrile toluene-4-sulfonate [5098-14-6] M 253.4, m 168-170 , 172 (dec), pKe 1.3. Colourless crysts on recrystn from MeCN (1.8g in lOOmL) using activated charcoal. Wash the crystals with dry Et20 and dry at 25 /lmm. Recovery of -80%. [Ferris et al. Org Synth Coll Vol V 32 7973.]... 

The synthesis of 5-aminothiazoles via the reaction of isocyanate derivatives with aminomalononitrile p-toluenesulfonate (AMNT) has been investigated. It was found that AMNT 12 reacted with alkyl and aryl isothiocyanates in l-methyl-2-pyrrolidine (NMP) to furnish 5-amino-2-(alkylamino)-4-cyanothiazoles (13a) and 5-amino-2-(arylamino)-4-cyanothiazoles (13b-c) in 44-81 % yields. " ... 

Hydrogen cyanide can also be added to the C=N bond to give iminonitriles or a-aminomalononitriles. ... 

To a cooled (0°), stirred suspension of 10.0 g. (0.0395 mole) of aminomalononitrile p-toluenesulfonate2 in 20 ml. of water is added 10.0 g. (0.204 mole) of sodium cyanide in 30 ml. of ice water. One minute (Note 1) after the addition of the sodium cyanide the precipitated product is collected by filtration and washed with 20 ml. of ice water. The solid is immediately dissolved (Note 1) in 30 ml. of boiling isobutyl alcohol, and the solution is stirred with 0.4 g. of Darco activated carbon (Note 2). The mixture is filtered rapidly through 10 g. of Celite filter aid, and the filter cake is washed with 10 ml. of hot isobutyl alcohol. The product that crystallizes on cooling is collected by filtration and washed with 10 ml. of isobutyl alcohol to give 0.95-1.1 g. (22-26%) of white needles, m.p. 181-183° (dec.). 

The present procedure is a modification of the original synthesis.9 Previous reports of the synthesis of aminomalononitrile are in error.2 Oximinomalononitrile was prepared by a modification of the procedure of Ponzio.3... 

This procedure provides a convenient synthesis of aminomalononitrile, which has been demonstrated to be a useful intermediate for the preparation of substituted imidazoles, thiazoles, oxazoles, purines, and purine-related heterocycles.2 It is also a convenient starting material for the preparation of diamino-maleonitrile.2, 4... 

Aminooxazole 11, readily obtained by reaction of N-Boc-L-Val-OH with aminomalononitrile p-toluenesulfonate and EDC in pyridine [5], was converted directly to bromooxazole 12 by in situ bromination via a nitrosamine intermediate. 

Another efficient 1,2-diamine for synthesis of cyanopyrazines is 2,3-diamino-3-phenylthioacrylonitrile 135, an adduct of thiophenol to aminomalononitrile tosylate (Scheme 37). The condensation with phenylglyoxal diethyl acetal affords a mixture of two possible isomers 136 and 137, whose regioselectivity is improved by addition of trifluoroacetic acid finally, the isomer 136 is isolated in 86% yield <2001SC725>. 

The synthetic strategy of preparing pyrazines by condensation of 2-keto aldoximes with a-amino nitriles is well represented by Taylor s pteridine synthesis, in which a variety of 2-amino-3-cyanopyrazine 1-oxides have been prepared by using aminomalononitrile <2002TL6747> as the amino nitriles. In the same fashion, some other a-amino nitriles, which are often the Strecker synthesis products, are converted into 2-aminopyrazine 1-oxides 160 (Scheme 44). The condensations are realized by treatment with iV-methylmorpholine <1993JOC7542>, and... 

Aminomalononitrile (6), an HCN trimer, no doubt forms as an intermediate in the base-catalyzed formation of DAMN from HCN (Section II,C,1). However, its rate of formation is slower than its reaction with an additional 1 mol hydrogen cyanide. Aminomalononitrile has been synthesized from malononitrile and shown to give DAMN upon treatment with cyanide (730SC33 730SC344). 

The above problems of concomitant formation of regioisomers (as well as products resulting from disproportionation of various dihydro intermediates) have been successfully surmounted by an unequivocal synthesis of 2-amino-3-cyano-5-halomethylpyrazines (16a,b) and their corresponding 1-oxides (28a,b), which can then be utilized for the construction of isomer-free 6-substituted pteridines and pterins (Scheme 3.3a). Thus, condensation of / -chloropyruval-doxime or / -bromopyruvaldoxime, derived from diketene by chlorination or bromination, respectively, with aminomalononitrile tosylate in 2-propanol gives the 2-amino-3-cyano-5-halomethylpyrazine 1-oxides (28a) and (28b). Deoxygenation to (16a) and (16b) is readily accomplished with phosphorus trichloride [47]. 

Quaternization of the sulfur atom followed by reaction with mercuric cyanide produces the corresponding 2-aminomalononitrile.64171... 

Amino-2-deoxy-i>-glucose, conversion of hydrochloride to 2-acetamido-2-deoxy-D-glucose, 46, 2 Aminomalononitrile from oximinomalo-nonitrile and aluminum amalgam, 48,2... 

Hydrogen cyanide, H-C=N , is a colorless, extremely toxic, volatile liquid, mp -13.4°C, bp -1-25.6 °C, with a high dielectric constant (107 at 25 °C). It functions as a weak acid Ka = 4.9 x 10 °). It is made by acidifying aqueous solutions of cyanides or industrially by the exothermic reaction of methane with ammonia in a fast flow/rapid quench system (equation 16). Hydrogen cyanide polymerizes readily nnder a variety of conditions hydrogen cyanide oligomers include the trimer aminomalononitrile and the tetramer diaminomaleonitrile (Figure 8). 

An intermediate in this reaction sing anhydrous hydrogen cyanide and ammonia was diaminomaleonitrile (67MI40901) and the same compound was also obtained from aminomalononitrile and hydrogen cyanide (66JA3829). UV radiation of the maleonitrile... 

Aminomalononitrile (readily made in 45-50% yield by reduction of the oximino compound with aluminium amalgam) condenses with formamidine acetate in ethanol to give 5-amino-4-cyanoimidazole in 35% yield [34]. 

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