Synthesis of Indoles from o-Haloanilines
Assia Chebieb1,2, Young Gyu Kim3, Jin Kun Cha1
1Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States.
Abstract:
A convenient method for the synthesis of indoles has been developed by the sequential orchestration of the cross-coupling reaction of o-haloaniline and PIFA oxidation of the resulting 2-alkenylanilines. A highlight of this two-step indole synthesis is a modular strategy which is applicable to both acyclic and cyclic starting materials. Particularly noteworthy is the regiochemistry that is complementary to the Fischer indole synthesis and related variants. Direct preparation of N-H indoles with no N-protecting group is also advantageous.
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