Aryl hydrazide beyond as surrogate of aryl hydrazine in the Fischer indolization: the synthesis of N-Cbz-indoles, N-Cbz-carbazoles, and N,N'-bis-Cbz-pyrrolo[2,3-f]indoles.

Aryl hydrazides underwent the Fischer indolization reactions, while the N-carbamate group(s) remained intact to directly provide N-Cbz-indoles. This new method allowed the synthesis of various N-Cbz-carbazoles and N,N'-bis-Cbz-pyrrolo[2,3-f]indoles.