Chlorine-nitrogen bonds

On the other hand, oxidizing fluonnating agents like silver difluoride, xenon difluoride, or bromine trifluoride replace one chlorine group and then cleave the sulfur-nitrogen bond [56],... 

The electrochemical cyclization reaction is less successful with the N-(3-phenylallyl)acetanilide 60 which has two potential bond cleavage sites from the radical-anion [173]. Carbon-nitrogen bond cleavage with loss of a 3-phenylallyl radical, leaving an amide nitrogen anion, is favoured over carbon-chlorine bond cleavage. 

The kinetic and other evidence obtained suggest that the carbon-nitrogen bond formation is the consequence of a nucleophilic interaction of an Af-phenylchlorohydroxylamine intermediate 135, formed in the second reaction step from 134, and the acyl halide, which leads to an Af-acyl-Af-chlorophenylhydroxylamine cation intermediate 136. The latter loses chlorine with the formation of 137. 

As operation with gaseous chlorine is dangerous and inconvenient, Corey Kim oxidations are normally performed by oxidation of dimethyl sulfide with /V-chIorosuccinimide rather than with chlorine. This results in the formation of a different kind of active DMSO species, in which a sulfur-nitrogen bond is present. 

Both IL3 and IL5 iodanes may formally eliminate the equatorial ligand as a cation in the resulting IL2 and ILj species bonding is still hypervalent, with elongated weak bonds. These iodates have mostly iodine-chlorine or iodine-nitrogen bonds although some of them are useful reagents, they will not be discussed here. 

Sultams can also be prepared by decomposition of the appropriate halo-and hydroxyalkanesulfonamides the cyclisations involve carbon-nitrogen bond formation, as illustrated by the formation of the sultam (179). In this reaction, the sulfonyl chlorine atom is more reactive towards nucleophilic attack than the alkyl chlorine and consequently reacts first (Scheme 74). 

The nucleophilic, stepwise displacement of chlorine from cyanuric chloride is usually the first method considered for preparation of 1,3,5-triazine derivatives (see Section 6.12.5.1.4). When this approach is not applicable, construction of the 1,3,5-triazine ring from various subunits by formation of carbon-nitrogen bonds is the alternative approach. No new synthetic strategies have emerged over the past decade and synthetic routes are based on the same f undamental principles described in previous reviews. 

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