Formation of the nitrogen-halogen bond

Diethyl diazomalonate 389 A mixture of diethyl mesoxalate hydrazone (20 g), dry, freshly precipitated silver oxide (100 g), magnesium sulfate (45 g), and tetrahydrofuran (300 ml) is shaken vigorously at room temperature for 4 h and then filtered. The solids are washed with tetrahydrofuran and the filtrates are united and concentrated in a rotary evaporator. Finally distillation affords diethyl diazomalonate (17.6 g, 89 %), b.p. 58°/0.3 mm, m.p. 9°, D241.4650. The methyl ester is obtained analogously. 

Diazirines, containing an unsaturated three-membered ring, are cyclic isomers of aliphatic diazo compounds they are colorless and stable to acids.390 The parent diazirine itself (cyclodiazomethane) is prepared by the action of sodium hypochlorite on methylenediamine.306 

Elemental chlorine and bromine, and alkali and alkaline-earth hypochlorides are used for JV-halogenation of amines or amides or tert-butyl hypochlorite, 395 may be usec for halogenation in an organic solvent. The Table on p. 598 illustrates uses of the individual halogenating agents. 

JV-Iodo amides are prepared exclusively by reaction of JV-silver salts with iodine. Occasionally the nitrogen-halogen bond has been created by trans-halogenation from, e.g., dichlorourea396 or JV-bromo amides.397 JV-Chloro-succinimide has been recommended for halogenation of sensitive amines in the steroid series.398 

Alteration of nitrogen groups in carbon-nitrogen compounds 

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