Alkyl cyanides radical

DL-Alk-2-enopyranos-4-uIose, 2,3-dideoxy-synthesis, 1, 426 Alkoxy nitroxide radicals pyridines ESR, 2, 146 Alkyl cyanides trimerization, 3, 503 Alkylating agents as pharmaceuticals, 1, 157 Alkylation... 

Relation to Amines.— When the alkyl cyanides are treated with nascent hydrogen an alkyl amine is formed in which the alkyl radical has one carbon more than the alkyl radical of the cyanide. 

A free radical can add to CO or an isocyanide (RNC) in the course of a free-radical cyclization reaction, too, to give an acyl radical (RC=0) or an iminyl radical (RC=NR), either of which can undergo further reactions. In the following example, an alkyl radical adds to the terminal C of f-BuNC to give an iminyl radical. The iminyl radical then fragments to give t-Bu- and an alkyl cyanide N=CR. In a different substrate, the iminyl radical may undergo an addition or an abstraction reaction instead. 

Cyanates contain the OCN group. Inorganic cyanates that are formed industrially by the oxidation of cyanide salts hydrolyze in water to form ammonia and bicarbonate ion. Alkyl cyanates are insoluble in water and form cyanurates. Alkyl isocyanates contain the OCN radical, are formed from cyanates, and, like cyanates, are readily hydrolyzed. Thiocyanates (SCN group) are formed from cyanides and sulfur-containing materials and are relatively stable. 

Generation of aryl radicals by reduction of aryl halides in the presence of some nucleophiles, particularly alkyl or aryl sulphide ions and cyanide ions, leads to bond formation with the generation of a new radical-anion. Overall, a reaction between the initial aryl halide and a nucleophile is triggered at the cathode and is an equivalent of the Sr I process. It proceeds in stages according to Scheme 4.6 [156] and requires only a catalytic concentration of radical-anion. The reaction can... 

Acyl cyanides1708 can be prepared by treatment of acyl halides with copper cyanide. The mechanism is not known and might be free-radical or nucleophilic substitution. The reaction has also been accomplished with thallium(I) cyanide,1709 with MejSiCN and an SnCl4 catalyst,1710 and with Bu3SnCN,1711 but these reagents are successful only when R = aryl or tertiary alkyl. KCN has also been used, along with ultrasound,1712 as has NaCN with phase transfer catalysts.1713 OS III, 119. 

From the determination of the molecular refractions of a large number of organic compounds containing tervalent arsenic, the atomic refraction of arsenic in each compound has been calculated,10 the values obtained varying from 9-2 to 14-39. Hydrogen, chlorine and alkyl groups in an arsine exert about the same influence on the atomic refraction of arsenic, but replacement of any of these by aryl groups causes an increase in the atomic refraction. The opposite effect results from substitution by a cyanide, oxalate or alkoxyl radical. 

Linkers that enable the preparation of y-lactones by cleavage of hydroxy esters from insoluble supports are discussed in Section 3.5.2. Resin-bound y-lactones have been prepared by Baeyer-Villiger oxidation of cyclobutanones [39], by intramolecular addition of alkyl radicals to oximes [48], by electrophilic addition of resin-bound sele-nenyl cyanide or bromide to 3,y-unsaturated acids (Figure 9.2 [100]), and by palladium-mediated coupling of resin-bound aryl iodides with allenyl carboxylic acids (Entry 10, Table 5.7 [101]). 

We will now consider a third type of radical—cyanide-stabilized alkyl radicals. 

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