Allyl cyanide, reaction

Vinylacetic acid. Place 134 g. (161 ml.) of allyl cyanide (3) and 200 ml. of concentrated hydrochloric acid in a 1-htre round-bottomed flask attached to a reflux condenser. Warm the mixture cautiously with a small flame and shake from time to time. After 7-10 minutes, a vigorous reaction sets in and the mixture refluxes remove the flame and cool the flask, if necessary, in cold water. Ammonium chloride crystallises out. When the reaction subsides, reflux the mixture for 15 minutes. Then add 200 ml. of water, cool and separate the upper layer of acid. Extract the aqueous layer with three 100 ml. portions of ether. Combine the acid and the ether extracts, and remove the ether under atmospheric pressure in a 250 ml. Claisen flask with fractionating side arm (compare Fig. II, 13, 4) continue the heating on a water bath until the temperature of the vapour reaches 70°. Allow the apparatus to cool and distil under diminished pressure (compare Fig. II, 20, 1) , collect the fraction (a) distilling up to 71°/14 mm. and (6) at 72-74°/14 mm. (chiefly at 72 5°/ 14 mm.). A dark residue (about 10 ml.) and some white sohd ( crotonio acid) remains in the flask. Fraction (6) weighs 100 g. and is analytically pure vinylacetic acid. Fraction (a) weighs about 50 g. and separates into two layers remove the water layer, dry with anhydrous sodium sulphate and distil from a 50 ml. Claisen flask with fractionating side arm a further 15 g. of reasonably pure acid, b.p. 69-70°/12 mm., is obtained. 

Some organosilicon compounds undergo transmetallation. The allylic cyanide 461 was prepared by the reaction of an allylic carbonate with trimethylsi-lyl cyanide[298]. The oriho esters and acetals of the o. d-unsaturated carbonyl compounds 462 undergo cyanation with trimefhylsilyl cyanide[95]. 

A subsequent publication by Blechert and co-workers demonstrated that the molybdenum alkylidene 3 and the ruthenium benzylidene 17 were also active catalysts for ring-opening cross-metathesis reactions [50]. Norbornene and 7-oxanorbornene derivatives underwent selective ring-opening cross-metathesis with a variety of terminal acyclic alkenes including acrylonitrile, an allylsilane, an allyl stannane and allyl cyanide (for example Eq. 34). 

Phenylacetonitriles can be induced to undergo Michael reactions with unactivated alkenes. For example, propenylarenes, formed in situ from allylarenes, react with phenylacetonitriles to form 3-aryl-l-cyano-2-methyl-l-phenylpropanes (70-98%) [3] by a procedure analogous to 6.4.1.B, Similarly, the nitriles react with alkynes giving allyl cyanides (80-95%) [38]. 

In the pyrolysis of pyrrole (8), two isomerization reactions are observed by which cw-crotononitrile and allyl cyanide are produced (89JPC5802). 

Allyl cyanide. Into a 2-litre three-necked flask, provided with a sealed stirrer and two long double surface condensers, place 293 g (210 ml, 2.42 mol) of freshly distilled allyl bromide, b.p. 70-71 °C (Expt 5.54) and 226 g (2.52 mol) of dry copper(i) cyanide (Section 4.2.23, p. 429). Warm the flask on a water bath so that the allyl bromide refluxes but do not stir at this stage. Immediately the vigorous reaction commences (after 15-30 minutes), remove the water bath and cool the flask in a bath of ice and water the two double surface condensers will prevent any loss of product. When the reaction subsides, start the stirrer and heat the mixture on the water bath for 1 hour. Remove the condensers and arrange the apparatus for distillation close one neck with a stopper. Heat the flask in an oil bath, and distil the allyl cyanide with stirring it is advisable to reduce the pressure (water pump) towards the end of the distillation to assist the removal of the final portion of the allyl cyanide from the solid residue. Redistil and collect the pure allyl cyanide at 116-121 °C. The yield is 140 g (86%). 

Substituted propenes CH2=CHCH2R, namely allylbenzene, allyl cyanide, and hexene-1 R = Ph, CN, n-Pr), were shown to yield stable a-alkylrhodium (III) porphyrins in moderate yields according to reaction (43) [269]. An isomerization and an attack on a saturated CH bond as shown in Eq. (20) could be the reason for the outcome of this type of reaction which is different to the examples shown in Eqs. (41) and (42). 

One potential problem in the reactions of stabilized allylic or propargylic carb-anions is the dimerization of the starting material if the carbanions are not formed stoichiometrically. Alkenes substituted with electron-withdrawing groups are good Michael acceptors, to which nucleophiles will undergo conjugate addition. For instance, the Baylis-Hillman reaction of allyl cyanide with benzaldehyde requires careful optimization of the reaction conditions to avoid dimerization of the nitrile (Scheme 5.12). This problem is related to a common side reaction of Michael additions reaction of the product with the Michael acceptor (Scheme 10.21). 

Scheme 5.12. Baylis-Hillman reaction of allyl cyanide [110],...

The formation of olefinic nitriles from allylic halides is best accomplished with dry, powdered cuprous cyanide rather than with alcoholic alkali cyanides, with which side reactions such as isomerization and alcoholysis of the double bond are particularly bothersome. With cuprous cyanide the yields in the synthesis of allyl cyanide and methal-lyl cyanide are 84% and 86%, respectively. Higher allylic halides are subject to allylic rearrangements thus cuprous cyanide acts on crotyl halide (CH,CH CHCHjX) and methylvinylcarbinyl halide (CH,CHXCH = CH,) to produce the same mixture of isomeric nitriles (9 1) regardless of which halide is treated. Numerous cyanides of the allylic type (Cj-Ci4) have been prepared, although the possibility of an isomerization has not been considered. A similar isomerization has been observed in the reaction of sorbyl chloride and potassium cyanide. ... 

Tridentate salen ligands (10) derived from 1 have given excellent results in the enantiocontrol of the hetero Diels-Alder addition reaction of dienes with aldehydes (eq 7) and in the asymmetric additions of TMS-azide to mc5o-epoxide and trimethylsilyl cyanide to benzaldehyde (up to 85% ee). Phosphino-oxazolines derived from 1 have been employed for the asymmetric control of palladium-catalyzed allylic substitution reactions products of 70-90% ee were obtained. Photolysis of crystalline adducts of enantiomerically pure 1 with prochiral alcohols results in asymmetric inductions of up to 79% in a rare example of a solid-state enantioselective reaction. ... 

A mixture of 358 g. (4.0 moles) of cuprous cyanide and 500 ml. of nitrobenzene is stirred and heated to 125-130° while 543 g. (6.0 moles) of /8-methylallyl chloride is added carefully in 25-50-ml. portions. The exothermic reaction from each portion of chloride is allowed to subside before the next portion is added. The mixture is heated under reflux for 30 minutes, cooled, and filtered. The filtrate is fractionally distilled to give a 58% yield (based on cuprous cyanide) of j8-methyl-allyl cyanide boiling at 136.2-136.4°, 1.4202,... 

SM(123)385>. Similarly, the reaction of 374 with allyl cyanide 397 furnished the cyanomethyl-containing thione 398 (Scheme 53) <2004TL2813>. 

Allyl Cyanide, Iso-thio-cyanate, etc.—From allyl chloride or the iodide there may be prepared by the customary reactions allyl cyanide and other of the cyanogen compounds. With potassium cyanide allyl iodide yields allyl cyanide. The reaction, however, instead of yielding a cyanide of the expected constitution is accompanied by a shifting of the double bond to the second carbon so that the cyanide has a constitution unlike that of the iodide from which it is made. 

In this series of reactions there occurs a shifting of the double bond from the first to the second carbon atom either in the allyl cyanide or when this is hydrolized to the acid for the acid obtained is crotonic acid which as we shall see has the constitution of A2-butenoic acid. 

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