Allyl cyanamide

The photosensitized oxidation of allylthiourea with erythrosin or eosin gave three products, the sulphinic acid (207), allyl cyanamide, and sulphuric... 

Alkylation with a vatiety of common alkyl halides oi sulfates gives stable dialkylcyanamides. However, the intermediate monoalkylated compounds usually cannot be isolated and cychc trimers or cotrimers with cyanamide ate obtained (13). The reaction can be carried out efficientiy in water or alcohol. Allyl chloride is an especially useful reagent, producing diallylcyanamide [538-08-9J (4). 

A convenient way of obtaining secondary amines without contamination by primary or tertiary amines involves treatment of alkyl halides with the sodium or calcium salt of cyanamide NH2—CN to give disubstituted cyanamides, which are then hydrolyzed and decarboxylated to secondary amines. Good yields are obtained when the reaction is carried out under phase-transfer conditions. The R group may be primary, secondary, allylic, or benzylic. 1, co-Dihalides give cyclic secondary amines. 

Activation of allyl chloride to genotoxic substances appears to involve aldehydes, since inhibition of aldehyde dehydrogenase by cyanamide increases the mutagenic activity in Salmonella typhimurium TAIOO on the other hand neither SKF525 nor 1,1,1-tri-chloropropene-2,3-oxide affect the mutagenicity, so that metabolic activation via an epoxide is unlikely (Neudecker Henschler, 1986). 

Diallyl amine has been prepared from allyl amine and allyl bromide,1 and from allyl amine and allyl chloride.2 Experiments on these methods showed that the resulting product contained relatively large amounts of triallyl amine and mono-allyl amine and it was very difficult to isolate pure diallyl amine. The above synthesis from diallyl cyanamide, which has recently appeared in the literature,3 is more satisfactory than the older methods. 

To the solution of sodium cyanamide thus prepared, 380 g. (3.14 moles) of allyl bromide (Note 3) and 660 cc. of 95 per cent alcohol are added. The mixture is then heated on a water bath with good stirring until it refluxes gently, and the heating and stirring are continued for two and one-half hours. Then the reflux condenser is replaced by one set downward for distillation. The stirring is continued and the alcohol is distilled until about 500 cc. has been collected. The distillate may be discarded or used for the recovery of alcohol (Note 4). 

Palladium-mediated cydization based on the reactivity of o-alkynyl or alkenyl-phenyl isonitriles have been developed [105]. On the basis of their earlier studies on the three-component synthesis of allyl aryl cyanamides [106], Yamamoto and co-workers reported a palladium-catalyzed three-component coupling reaction of 2-alkynylisocyanobenzenes 122 with allyl methyl carbonate and trimethylsilylazide leading to N-cyanoindoles 125 [107]. One of the key steps of the proposed mechanism is the formation of 7i-allylpalladium carbodiimide 123 and its isomerization to rc-allylpalladium cyanamide complex 124 (Scheme 8.50). 

The iodocyclization of acyclic unsaturated isoureas containing (S )-phenylethylamine as the chiral auxiliary gave chiral cyclic isoureas, which are masked 1,2-diamines. Starting from (S)-phenyl-ethylamine, the corresponding cyanamide was easily obtained, which was then converted, after allylation, to the corresponding isourea. The iodocyclization of the isourea derived from (S)-phenylethylamine afforded an equimolar diastereomeric mixture of 4,5-dihydroimidazoles 4 in 90% yield, which were easily separated by chromatography167. 

The von Braun reaction involves the cleavage of tertiary amines by cyanogen bromide to give an alkyl bromide and a disubstituted cyanamide, and can be applied to many tertiary amines.Usually, the R group that cleaves is the one that gives the most reactive halide (e.g., benzyl or allyl). For simple alkyl groups, the smallest... 

Tertiary amines are cleaved with BrCN to give an alkyl bromide and a disubstituted cyanamide (Scheme 21). This process is called the von Braun reaction. Many examples have been reviewed. Tertiary amines with different R groups cleave so that the most reactive alkyl bromide is formed. Benzyl and allyl cleave better than alkyl, lower alkyl cleaves better than higher alkyl and aryl is not cleaved at... 

Attempts to demethylate himbacine with a variety of reagents under several conditions were unsuccessful but dihydrohimbacine was readily converted by cyanogen bromide into the cyanamide (XXVI). This was stable to acid and only slowly hydrolyzed by alkali but catalytic hydrogenation afforded dihydrohimbeline in good yield. By standard methods the following iV-substituted derivatives were prepared ethyl, p-hydroxyethyl (p-nitrobenzoate and trimethylgallate), allyl, m-butyl, ethoxycarbonylmethyl, cyclohexyl, benzyl, /3-phenylethyl, y-phenyl-propyl, and phenylcarbamido. 

The reaction of 3jL with 10% excess benzyl bromide or 34 with 10% excess methyl iodide gave the same product, N-benzyl-N-methyl cyanamide (47). The reactions of 33 with 10% and 55% excess allyl bromide afforded N-allyl-N-methyl cyanamide (48) and N,N-diallyl cyanamide (49), respectively. The reaction of 32 with 28% excess of allyl iodide furnished N-allyl-N-propyl cyanamide (50). 

The reaction of i31 with 10% and 55% excess allyl bromide afforded N-allyl-N-methyl cyanaraide (48) and N,N-diallyl cyanamide (49), respectively. 

The reaction of 32 with 28% excess of allyl iodide gave N-allyl-N-propyl cyanamide (50). 

Kamijo and Yamamoto developed a palladium-catalyzed three-component synthesis of N-cyanoindoles (131) (Scheme 5.39) [81]. The reaction of a 2-alkynyliso-cyanobenzene (132), allyl methyl carbonate, and trimethylsilylazide in the presence of Pd2(dba)3 (2.5 mol%) and tri(2-furyl)phosphine (10 mol%) at 100 °C afforded the N-cyanoindoles 131 in good yield. Key steps of this reaction involved the formation of jt-allylpalladium complex 133, its Curtius-like rearrangement to intermediate 134, and subsequent isomerization to the Jt-allylpalladium cyanamide complex 135. A wide range of functional groups is tolerated at the para, meta, and even ortho positions of the aromatic ring. 

Allylic thermal rearrangement of cyanamides constitutes a method for the formal 1,3-isomerization of allylamines (Scheme... 

Chloromethane — Methyl chloride 3-Chloropropene Allyl chloride Cyanamide N-C 1.346 C-N, 1.160 MW... 

Unusual species have been obtained from the reaction between dialkyl cyanamides and [Ni(CO)4], which form [Ni(CO)R2NCN]2 complexes, (R = CH3, C2H5) for which a pseudo-ir-allylic structure (XLV) has been... 

Apart from the jr-allyl ligands there are several groups whose bonding to the metal contains M-C bonds and which are 3-electron ligands. For example, treatment of nickel carbonyl with dialkyl cyanamides gives dimeric complexes for which structure 2.28 has been proposed [89]. 

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