Synfacts 2006(12): 1217-1217  
DOI: 10.1055/s-2006-955570
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart · New York

Phenethylamine Trimerization to Pyrroles

Contributor(s): Victor Snieckus, Todd Macklin
X. Wan, D. Xing, Z. Fang, B. Li, F. Zhao, K. Zhang , L. Yang, Z. Shi*
Peking University, Beijing; State Key Laboratory of Organometallic Chemistry and East China Normal University, Shanghai, P. R. of China
Further Information

Publication History

Publication Date:
22 November 2006 (online)

Significance

Reported is the palladium-catalyzed trimerization of commercial phenethyl­amines to give symmetrical pyrroles in synthetically useful yields. Remarkably, the reaction involves the selective activation of two sp3 C-H bonds leading to an overall cleavage of at least 12 C-H and C-N bonds and formation of five new C-N, C-C, and C=C bonds in a one-pot reaction. Electron-donating groups increase the efficiency of this reaction. With respect to mechanism, imine formation and deamination are reactions which are known to occur under the conditions described (S.-L. Murahashi, N. Yoshimura, T. Tsumiyama, T. Kojima J. Am. Chem. Soc. 1983, 105, 5002-5011). The structure of one of the pyrrole products has been verified by X-ray crystallographic analysis.