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.