Displacement, of azide ion

Insertion into N—bonds by alkoxycarbonylnitrenes is a facile reaction, but is hampered by nucleophilic displacement of azide ion when alkoxycarbonyl azides are used as the nitrene precursor. Haf-ner obtained a 52% yield of phenylhydrazoformate, PhNHNH-COOC2H5, by thermolysis of ethyl azidoformate in aniline Aroyl azides have also been used Horner obtained a 14% yield of N-phenyl-iV -benzoylhydrazine by photolys ng benzoyl azide in aniline. With more nucleophilic amines, it is better to use the a-elimination route to alkoxycarbonylnitrenes . Using this method, yields of... 

A -AIkyl-2-azidobenzothiazolium tetrafluoroborates exhibit ambident reactivity with nucleophiles. With hard nucleophiles, e.g. hydroxide ion, methoxide ion, or dimethylamine, reaction occurs at the 2-position with displacement of azide ion. In contrast, softer nucleophiles, e.g. azide ion, cyanide ion, toluene-p-... 

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