Azides may be converted to amines by hydrogenation, but another possibility is the
Staudinger Reaction, which is a very mild azide reduction. As there are
a variety of methods for preparing azides readily, the Staudinger
Reaction makes it possible to use
-N3 as an -NH2 synthon.
Mechanism of the Staudinger Reaction
Triphenylphosphine reacts with the azide to generate a phosphazide, which
loses N2 to form an iminophosphorane. Aqueous work up leads to the
amine and the very stable phosphine oxide.
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2,2′-Dipyridyl diselenide catalyzes a direct reaction of carboxylic acids with
azides and trimethylphosphine at room temperature. The mechanism of the process,
which is not an aza-Wittig reaction, has been elucidated.
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Three-Component, One-Pot Sequential Synthesis of 1,3-Disubstituted
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