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Updated: Aug 14, 2025

Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate
Published on: April 24, 2018
Organocalcium Hydride-Catalyzed Intramolecular C(sp3)-H Annulation of Functionalized 2,6-Lutidines
Shuo Li1, Xian Xu1, Qianlin Sun1
1Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
Abstract:
This work reports an intramolecular C(sp3)-H annulation of functionalized 2,6-lutidines catalyzed by an organocalcium hydride [{(DIPPnacnac)CaH(thf)}2] (DIPPnacnac = CH{(CMe)(2,6-Pr2-C6H3N)}2). This reaction constitutes a streamlined approach for producing a new family of tetrahydro-1,5-naphthyridines and hexahydropyrido[3,2-b]azocines derivatives in good to excellent yields with high atom efficiency and broad substrates scope. A calcium alkyl complex was isolated from the stoichiometric reaction between calcium hydride and the substrate through deprotonation, which was structurally characterized and confirmed as the catalytic intermediate.
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