Cyanamide benzyl

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. 

Very few publications are available on the reactivity of substituents attached to the ring nitrogen and sulfur atoms of thiadiazole. The N-benzyl group in (107) can be removed with AICI3 to give the cyanamide (108) and the antiviral compound (109) on further treatment with base <92MI 410-01 >. 

Another standard method of producing a fused pyrimidine ring is reaction with formamidine, which always provides for no substituent at position 2. However 391 reacts with chloroformamidine, obtained by reaction of cyanamide and HCI, to produce a variety of benzyl derivatives 392 (Equation 147) <2004JHC941> that mimic guanine analogs. 

Cyanamid [(4-Methoxy-benzyl-amino)-methylthio-methylen]-E4, 1298 [(RS)3C = N-CN + Amin]... 

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). 

We now wish to report that replacing the O-potassium S-alkyl cyanothioimidocarbonates with -alkyl and benzyl -potassium cyano-imidocarbonate afforded the synthesis of the previously unknown titled carbamates or the N,N-disubstituted cyanamides. 

In summary, depending on reaction condition, we have described a novel and versatile direct synthesis of alkyl N-cyano-N-substituted carbamates or N,N-disubstituted cyanamides. The required intermediates can be prepared in good yields from cyanamide, carbon disulfidtj potassium hydroxide, alkyl or benzyl alcohols and alkyl or benzyl halides which are readily available and inexpensive. 

Amination. In a single step benzylic amination is achieved with NBS with catalytic amounts of FeCl2. Aminating agents include carboxamides and sulfonamides. A-Cyano sulfilimines are formed by reaction of sulfides with cyanamide in the presence of NBS, probably involving 5-bromination. ... 

Dibenzylamine 499 Finely ground, commercial calcium cyanamide (14.6 g 50% CaCN2 content) is suspended in 70% alcohol (100 ml), treated with benzyl chloride (25.3 g), and heated under reflux for 12 h. The solid material is then filtered off and washed with alcohol, and the filtrate is saturated with gaseous hydrogen chloride and then heated in an autoclave at 140° for 4-5 h. Dibenzylamine hydrochloride separates as large plates (13 g, 55%). 

Labelled cyanogen bromide ( CNBr) has been used by Westerberg and Langstrom to synthesize several aromatic cyanates, and cyanamides, a 1-cyanopyridinium bromide and phenyl and benzyl thiocyanates in good yields in a few minutes (Scheme 5). The yields for each reaction are in the parentheses. 

Stanislao Cannizzaro (Palermo, Sicily, 1826-Rome, 10 May 1910) studied in Palermo and Naples. In 1847 he took part in the Rebellion. In 1850 he became Piria s assistant in Paris and in 1851 published his first research, on cyanogen chloride and cyanamide, done jointly with Cloez in Chevreul s laboratory. In 1852 he was appointed in Alessandria and in 1853 published an important researdi on the action of caustic potash on benzaldehyde, obtaining potassium benzoate and benzyl alcohol ( Cannizzaro s reaction ) 2C,H5CHO+KOH=C.HsCOOK+C,H8CH,OH. In 1855 he became professor in G noa, where at fimt there was no laboratory, and there he wrote his famous pamphlet. In i860 he joined Garibaldi at Palermo. In 1861 he became professor in Palermo and in 1870 in Rome, where he was created senator. ... 

The use of the related AT-cyano group may also be mentioned here. The reaction between cyanamide and the benzylic halide (14) in the presence of an excess of sodium hydroxide is reported to give the azocine derivative (15) directly. Removal of the iV-cyano group was brought about by treatment with sodamide in xylene [102]. The overall yield was slightly inferior to that obtained in a similar sequence using the benzyl group for protection. 

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