Annulated Pyridines Research Articles

Convenient Formation of Six- to Nine-Membered Carbocyclic Rings by 2-Pyridyl Radical Cyclization: A Generalized Synthesis of Pyridine-Fused Linear Tricyclic Systems

Intramolecular cyclization of 2-pyridyl radicals derived from 2-bromopyridin-3-yl substituted methylenecycloalkanes 19-22, vinylcycloalkanols 23 and 24, allylcycloalkanols 26-28, and butenylcycloalkanols 32-34 proceed via 6-, 7-, 8-, and 9-endo-trig pathways, giving six-, seven-, eight-, and nine-membered ring annulated pyridines respectively. However, the vinyl cyclopentanol 25 produced only the 6-exo-cyclized product 46, while the substituted allylcyclohexanol 29 and the butenylcyclohexanol 31 failed to cyclize, producing only the double bond isomerized debrominated olefins. Thus the method provides a useful entry to diverse classes of fused pyridines, with the ring size of the cycloalkane and the presence of additional substituents in the ring playing an important role in determining the outcome of the reactions.

An efficient one-pot synthesis of annulated pyridines utilising a directed ortho-metallation/transmetallation approach

The ortho-alkylation of Boc-protected aminopyridines with α,ω-dihaloalkanes followed by in situ cyclisation, resulted in the corresponding annulated pyridine derivatives in good to excellent yields. The effect of the alkylating and chelating agents, the transmetallation additives and the directing group was examined.

Heteroaryl Radicals. Part 1. Synthesis of Linear Pyridine‐Fused Ring Systems by endo‐Selective 2‐Pyridyl Radical Cyclizations.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Heteroaryl radicals. Part 1. Synthesis of linear pyridine-fused ring systems by endo-selective 2-pyridyl radical cyclizationsThis paper has been dedicated to Professor U. R. Ghatak on the occasion of his 70th birthday.

Bu3SnH-induced 2-pyridyl radicals, derived from the 2-bromopyridinyl-substituted methylenecyclohexane 4 and also the vinyl- and the allyl-cyclohexanols 5 and 6, undergo endo-selective cyclizations to give six-, seven- and eight-membered-ring annulated pyridines 7, 11 and 12.

Microwave-accelerated three-component condensation reaction on clay: solvent-free synthesis of imidazo[1,2- a] annulated pyridines, pyrazines and pyrimidines

A rapid one-pot synthesis of imidazo[1,2- a] annulated pyridines, pyrazines and pyrimidines is described that occurs in the presence of recyclable montmorillonite K 10 clay under solvent-free conditions using microwave irradiation.

ChemInform Abstract: SYNTHESIS OF 2,6‐DISUBSTITUTED PYRIDINES, POLYPYRIDINYLS, AND ANNULATED PYRIDINES

Chemischer InformationsdienstVolume 13, Issue 52 Heterocyclic Compounds ChemInform Abstract: SYNTHESIS OF 2,6-DISUBSTITUTED PYRIDINES, POLYPYRIDINYLS, AND ANNULATED PYRIDINES K. T. POTTS, K. T. POTTSSearch for more papers by this authorM. J. CIPULLO, M. J. CIPULLOSearch for more papers by this authorP. RALLI, P. RALLISearch for more papers by this authorG. THEODORIDIS, G. THEODORIDISSearch for more papers by this author K. T. POTTS, K. T. POTTSSearch for more papers by this authorM. J. CIPULLO, M. J. CIPULLOSearch for more papers by this authorP. RALLI, P. RALLISearch for more papers by this authorG. THEODORIDIS, G. THEODORIDISSearch for more papers by this author First published: December 28, 1982 https://doi.org/10.1002/chin.198252239AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume13, Issue52December 28, 1982 RelatedInformation

Synthesis of 2,6-disubstituted pyridines, polypyridinyls, and annulated pyridines

Synthesis of 2,6-disubstituted pyridines, polypyridinyls, and annulated pyridines