Cyclopentadiene-phosphine/palladium-catalyzed cleavage of C-N bonds in secondary amines: synthesis of pyrrole and indole derivatives from secondary amines and alkenyl or aryl dibromides

Weizhi Geng; Wen-Xiong Zhang; Wei Hao; Zhenfeng Xi

doi:10.1021/ja308950d

Cyclopentadiene-phosphine/palladium-catalyzed cleavage of C-N bonds in secondary amines: synthesis of pyrrole and indole derivatives from secondary amines and alkenyl or aryl dibromides

J Am Chem Soc. 2012 Dec 19;134(50):20230-3. doi: 10.1021/ja308950d. Epub 2012 Dec 10.

Authors

Weizhi Geng¹, Wen-Xiong Zhang, Wei Hao, Zhenfeng Xi

Affiliation

¹ Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry, Peking University, Beijing 100871, China.

PMID: 23198876
DOI: 10.1021/ja308950d

Abstract

An efficient Pd-catalyzed cleavage of C(sp(3))-N bonds in secondary amines and a consequent C(sp(2))-N and C(sp(3))-N coupling process was developed. Various secondary amines could be used to react with alkenyl or aryl dibromides, affording pyrroles and indoles in high yields. Cyclopentadiene-phosphine ligands, a new type of P-olefin ligand, were found to be able to promote the efficiency of this Pd-catalyzed process remarkably. A reactive Pd complex coordinated with a cyclopentadiene-phosphine ligand was successfully isolated and structurally characterized.