Cyano compounds aliphatic

This chapter reports about an investigation on the catalytic gas-phase armnoxidation of u-hexane aimed at the production of 1,6-Ce dinitriles, precursors for the synthesis of hexamethylenediamine. Catalysts tested were those also active and selective in the ammoxidation of propane to aciylonitrile mtile-type V/Sb and SnA /Nb/Sb mixed oxides. Several A-containing compounds formed however, the selectivity to cyano-containing aliphatic linear Ce compounds was low, due to the relevant contribution of side reactions such as combustion, cracking and formation of heavy compounds. 

Cyano compounds (nitriles) R-C N 2260-2240 (w) (aliphatic) 2240-2220 (m) (aromatic, conjugated) Electronegative elements a-to the CsN group reduce the intensity of the absorption... 

A group of Russian workers [22 to 27] reported on the fluorination of mixtures of solid amines, amides, or cyano compounds with KF or CaF2. The reactions were carried out in a stream of F2 diluted with N2 at about -10 to +10°C. NF3 was one of the main products and was accompanied by fluorinated fragments of the compounds treated. The N-containing compounds studied include aliphatic amine hydrochlorides [22, 23], the amides of trifluoro- and difluoro acetic acid [24], potassium cyanate [25], silver and potassium thiocyanate [26], and a acetonitrile boron trifluoride complex [27]. 

Electrochemically generated nickel is very selective for the reduction of aromatic nitro compounds into anilines, in which alkenyl, alkynyl, halo, cyano, formyl, and benzyloxy groups are not affected.84 Sodium sulfide has been used for the selective reduction of aromatic nitro group in the presence of aliphatic nitro groups (Eq. 6.44).85... 

From 2-mercaptobenzoic Acid. The most widely used method of 1,3-benzo-TA synthesis is the reaction of 2-mercaptobenzoic acid with compounds containing a cyano group to afford various 2-substituted 1,3-benzo-TAs 56 [aryl and benzyl (57MI1), chloromethyl, and carboethoxymethyl (60MI1)]. Note that nitriles of aliphatic acids (acetonitrile and others) do not react in these conditions. The reaction of 2-mercaptobenzoic acid with... 

Cases are known where pyrazoles are formed from aliphatic diazo compounds and cyano-olefins,462,493 or nitro-olefins, the latter reaction being studied systematically by Parham and co-workers, who established that the relatively stable nitropyrazolines initially formed eliminate nitrous acid when heated with acid.484-486 (See also reference 486a.) When the diazo compound is gem-disubstituted, a pyrazole is formed by migration of one of the groups, which was... 

There are three major categories of this type of compound, in which the aliphatic part may be a perfluoroalkyl, an alkenyl or an alkynyl group two recent additions -with a cyano or a diazoacetate group - are promising reagents for future applications. 

A one-pot synthesis of 3,5-disubstituted 7-hydroxy-3//-l,2,3-triazolo[4,5-d]pyrimidines (130) has been carried out by using benzyl azide, cyano-acetamide, ethyl or methyl esters of the appropriate carboxylic acid, and sodium ethoxide as catalyst. The reaction proceeds via a 5-amino-l-benzyltriazole-4-carboxamide intermediate (85JHC1607). 7-Amino-3H-l,2,3-triazolo[4,5-d]pyrimidines 133 (R2 = H) were prepared starting from benzyl azide, malononitrile, and an aliphatic or aromatic nitrile, or by reaction of 130 with phosphorus oxychloride followed by amination. Compound 132 was formed in most reactions from two molecules of the 5-amino-4-cyano-l-benzyltriazole intermediate by an intermolecular nucleophilic at-... 

Reduction of NO. This Ti(ll) reagent reduces aromatic and aliphatic nitro compounds to amines in THF/r-butyl alcohol at 0° in yields of 85-95%. Halo, cyano, and ester groups are not reduced. 

As a preparative method the direct decarboxylation of olefinic acids is almost limited to the formation of styrenes and stilbenes from substituted cinnamic acids. Thermal decomposition of cinnamic acid gives styrene (41%). The yield is nearly quantitative if the reaction is carried out in quinoline at 220° in the presence of a copper catalyst. The yields of substituted styrenes where the aryl radical contains halo, methoxyl, aldehyde, cyano, and nitro groups are in the range of 30-76%. cis-Stilbene and cis-p-nitrostilbene are prepared in this way from the corresponding a-phenylcinnamic acids (65%). One aliphatic compound worthy of mention is 2-ethoxypropene, prepared by heating -ethoxycro-tonic acid at 165° (91% yield). The mechanism of acid-catalyzed decarboxylations of this type has been studied. Isomerization of the double bond from the a,/5- to the /5, y-position before decarboxylation very likely occurs in many instances. ... 

The condensation equilibrium is displaced to the right by removing the unsaturated cyano ester as it is formed by the addition of hydrogen cyanide The effect is analogous to the single-step formation and hydrogenation of a,/S-unsaturated cyanoacetic esters (method 394). The yields are good with most aliphatic ketones and aldehydes (49 75%), but poor results are obtained with aromatic carbonyl compounds and diisopropyl ketone. 

Nitriles are directly converted to esters by heating with an alcohol and sulfuric or hydrochloric acid. When water is absent, the imino ester salt is readily isolated (method 402). Aliphatic,aromatic, and heterocycliccyano compounds react in this manner. Most of the aromatic compounds contain a cyanomethyl group although the cyanide radical may be attached directly to the aromatic nucleus. Monosub-stituted malonic esters free from unsubstituted and disubstituted malonic esters are made from the corresponding a-cyano esters by this method. Malonic ester and disubstituted malonic esters have been similarly prepared. ... 

Titanium(II) reagents have also been used to reduce aliphatic nitro compounds to amines halo, cyano and ester groups are not reduced. Sodium borohydride, in the presence of catalytic amounts of nickel(II) chloride, reduces a variety of aliphatic nitro compounds to amines. Nickel boride (Ni2B) is an active catalyst for reductions of primary, secondary and tertiary nitro aliphatic compounds to amines. The reduction of nitrocyclohexane (45) yields cyclohexylamine (47) as well as small amounts of dicyclohexylamine (49), the latter being formed via reaction of intermediates (46) and (48 equation 28). 

The destabilization of sp -bound fluorine by p-jt repulsion activates fluorinated aromatic compounds totvard nucleophilic attack and subsequent substitution. The susceptibility of the carbon center toward nucleophiles is also enhanced by the negative inductive (—T) effect of fluorine. In particular, if the aromatic compound is also activated by —M electron-withdrawing substituents, for example a nitro or cyano group, in the ortho or para positions the fluorine is easily replaced by a variety of nucleophiles even under very mild conditions via a resonance stabilized Meisenheimer complex (Scheme 2.39). The ease of nucleophilic halogen replacement - F > Cl > Br > I - is in the opposite order to that for aliphatic nucleophilic substitution. 

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