Malonitrilic

Acceptors. Most common acceptor molecules such as tetracyanoethylene or tetracyanoqurno dime thane ate commercially available. However, TCNQ can be synthesized in high yield by a two-step synthesis involving a condensation of malonitrile with 1,4-cyclohexanedione followed by treatment with an oxidizing agent such as bromine or A-bromosuccinamide in pyridine solvent (23) (Fig. 6). 

F. Freeman, Chem. Kevs. 9, 591 (1969). Review of malonitrile chemistry. 

Other examples of CN/CC replacement are observed in reactions of l-phenyl-pyrimidin-2(l//)-one with active methylene compounds, such as diethyl malonate and benzoylacetate, giving in good yield 2-oxo-l,2-dihydro-3-pyridinecarboxylate and 3-benzoylpyridin-2(l H)-one, respectively (84CPB2942, 87H2223) (Scheme 8). In a similar way 4,6-dimethyl-1-phenylpyrimidin-2( 1 //)-one, 4,6-dimethyl-1 -phenylpyrimidine-2( 1 //)-thione and 4,6-dimethyl-1 -phenyl-2-phenylimino-1,2-dihydropyrimidine yield with malonitrile 2-amino-4,6-dimethyl-3-pyridinecarbonitrile. In a similar way 2,3-diarylpyrimidin-4(3//)-thiones give with malonitrile CN/CC replacement (84H763) (Scheme 8). The reaction takes a similar course as described in Scheme 7. 

CN/CC replacements were also observed when the pyrimidine ring is part of a bicyclic system. Reaction of quinazoline with active methylene compounds, containing the cyano group (malonitrile, ethyl cyanoacetate, phenylacetonitrile) gave 2-amino-3-R-quinoline (R = CN, C02Et, Ph) (72CPB1544) (Scheme 12). The reaction has to be carried out in the absence of a base. When base is used, no ring transformation was observed only dimer formation and SnH substitution at C-4 was found. 

A more detailed study of the reaction with malonitrile revealed that the yields are dependent of the molar ratio malonitrile/quinazoline. The yield increases from 29 (ratio 1.0) to 81% (ratio 2.0), suggesting that the mechanism of the ring transformation involves the contribution of 2 mol of malonitrile. Reaction of quinazoline 3-oxide with the above-mentioned active methylene compounds gives about the same results, although the yields are poor (Scheme 12) (73CPB1943, 75CPB746). 

CN/CC replacement has also been observed on treatment of pteridine with malonitrile or cyanoacetamide 6-amino-7-R-pyrido[2,3,-h]pyrazine (R = CN, CONH2) beingformed (73JCSP(1)1615) (Scheme 15). The reaction involves initial addition of the reagent to the N-3-C-4 bond, scission of the dihydro bond between N-3 and C-4 in the covalent adduct, and recycli-zation. This mechanism is fundamentally different from the mechanism mentioned in Scheme 14, where two molecules of the reagent were used for addition and where the bond breaking takes place between N-1 and C-2. 

Malonitril, n. malonitrile, malic nitrile (improperly but commonly) malononitrile, ma-lonic nitrile. 

The polymer produced is comprised of several compns. The simplest is the tetramer or Diamino-malonitrile, (HCN)a lab is 15% mp 184° (decompn). Sol in boiling w. A much more complicated, w insol. cryst material is also produced... 

Malonic acid, amino-, diethyl ester, HYDROCHLORIDE, 40, 24 Malonic acid, bts(hydroxymethyl)-, DIETHYL ETHER, 40, 27 Malonitrile, condensation with tetra-cyanoethylene, 41, 99 2-Mercaptopyrimidine, 43, 6S hydrochloride of, 43, 68 Mercuric oxide in preparation of bromo-cyclopropane, 43, 9 Mesityl isocyanide, 41,103 5-Methallyl-l,2,3,4,5-pentachlorocyclo-pentadiene, 43, 92 Methane, dimesityl-, 43, 57 Methanesiileinyl chloride, 40, 62 Methanesulfonic acid, solvent for making peroxybenzoic acid from benzoic acid, 43, 93... 

Tetracyanoethylene, condensation with malonitrile, 41, 99 Tetradecanedioic acid, 43, 39... 

The synthesis of pyrido[2,3-d]pyrimidin-7(8H)-ones has also been achieved by a microwave-assisted MCR [87-89] that is based on the Victory reaction of 6-oxotetrahydropyridine-3-carbonitrile 57, obtained by reaction of an Q ,/3-unsaturated ester 56 and malonitrile 47 (Z = CN). The one-pot cyclo condensation of 56, amidines 58 and methylene active nitriles 47, either malonitrile or ethyl cyanoacetate, at 100 °C for benzamidine or 140 °C for reactions with guanidine, in methanol in the presence of a catalytic amount of sodium methoxide gave 4-oxo-60 or 4-aminopyridopyrimidines 59, respectively, in only 10 min in a single-mode microwave reactor [87,88]... 

At 130°C or at ambient temperature and in the presence of bases, malonitrile gives rise to a very violent polymerisation. The stability of this dinitrile in the molten state (mp 32°C) decreases with the temperature rise and its fall in purity. It was assumed that decomposition never occurs below 100 C. However, when this compound was heated to 70-80°C for two months, this caused a very violent detonation. 

Fig. 4.9 A synthesis resulting in polypeptides (or compounds similar to polypeptides using amino-malonitrile and further adding hydrogen cyanide. In this process, R 15 may represent different side chains of amino acids...

The angularly fused pyridazino[l,6- ]quinazolines were prepared by tandem [6+0 (a), 6+0 (7)] cyclization of functionalized, diazotized anthranilic acid derivatives. Depending on the order of reacting ethyl benzoylacetate, malonitrile, and the diazotized anthranilonitrile, the pyridazino[l,6- ]quinazolines 103 or 105 were obtained by alkaline or thermal cyclizations, respectively (Scheme 11) <2001T1813>. 

Reagents and conditions i, n-BuLi, DMF ii, (Bun)2NPhCH2P+(Ph)3l, BuOK, CH2CI2 iv, malonitrile, EtOFl v, 1,3-diethyl-2-thiobarbutiricacid, EtOH... 

Organic cyanide compounds, or nitriles, have been implicated in numerous human fatalities and signs of poisoning — especially acetonitrile, acrylonitrile, acetone cyanohydrin, malonitrile, and succinonitrile. Nitriles hydrolyze to carboxylic acid and ammonia in either basic or acidic solutions. Mice (Mus sp.) given lethal doses of various nitriles had elevated cyanide concentrations in liver and brain the major acute toxicity of nitriles is CN release by liver processes (Willhite and Smith 1981). In general, alkylnitriles release CN much less readily than aryl alkylnitriles, and this may account for their comparatively low toxicity (Davis 1981). 

Reaction of melatonin with various aryldiazonium chlorides in ethanolic sodium acetate solution afforded arylazo-melatonin derivatives. Reactions of these products with either malonitrile or ethyl cyanoacetate formed the corresponding ary lam inotriazino[4,3-/z indole scaffolds 60-63 <2005BMC1847>. 

The coordinated dioxygen in 3 -Co(02) is nucleophilic and reacts with electron-poor organic substrates such as benzoyl chloride, malonitrile, and tetracyanoethylene to transfer a single oxygen atom. A mechanism involving a homolytic Co-0 bond cleavage has been proposed (33). The nucleophilic character of 3 -Co(02) was... 

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