Synfacts 2009(4): 0367-0367  
DOI: 10.1055/s-0028-1087893
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart ˙ New York

Lanthanide Triflate Catalyzed Hetero-annulation Route to Tetrahydroquinolines

Contributor(s): Victor Snieckus, Jignesh J. Patel
S. Murarka, C. Zhang, M. D. Konieczynska, D. Seidel*
Rutgers, The State University of New Jersey, Piscataway, USA
Further Information

Publication History

Publication Date:
23 March 2009 (online)

Significance

Described here is a lanthanide Lewis acid catalyzed synthesis of simple and fused tetrahydroquinolines from aniline ortho-­alkylidene malonates. The reaction appears to proceed by a redox process involving a 1,5-hydride shift followed by an intramolecular ring closure although mechanistic evidence was not provided. A β-keto ester derived starting material (one example; R³ ∂ R4) gave the product as a mixture of diastereomers (64:36). Diketone alkylidenes worked efficiently but with longer reaction times while the single case of a dinitrile alkylidene (R³ = R4 = CN) failed to give any product.