Nitrone-alkene Cycloaddition Research Articles

1,3-Dipolar cycloaddition of nitrones with nitriles.: Scope and mechanistic study

1,3-Dipolar cycloadditions of nitrones 1–6 with nitriles 14–16, proceeded under thermal as well as under high pressure conditions with complete regioselectivity to give Δ 4-1,2,4-oxadiazolines 17–19. In general, the cycloaddition seemed to be controlled by a HOMO(nitrone)- LUMO(nitrile) interaction. However, a crossover in the orbital control is probable observed with nitrile 16c. Nitrone-nitrile cycloadditions are normal type II cycloadditions so that the nitriles have a U-shaped reactivity curve. Kinetic study on solvent polarity and Hammett equation demonstrated that mechanistically the nitrone-nitrile cycloaddition is consistent with nitrone-alkene cycloaddition.

Chemoselective Intramolecular Nitrone‐Olefin Cycloaddition : An Efficient Route to Functionalized Cis Hydrindane Systems

AbstractIsoxazolidines 5a‐c and 8 were obtained via chemoselective nitrone‐olefin cycloaddition in suitably modified 1,4‐cyclohexadienes 1a‐c: 5a and 5c were transformed to highly functionalized cis‐hydrindanes.

ChemInform Abstract: Stereocontrolled Total Syntheses of (‐)‐Hobartine and (+)‐Aristoleline via an Intramolecular Nitrone‐Olefin Cycloaddition.

Chemischer InformationsdienstVolume 17, Issue 30 Natural Products ChemInform Abstract: Stereocontrolled Total Syntheses of (-)-Hobartine and (+)-Aristoleline via an Intramolecular Nitrone-Olefin Cycloaddition. G. W. GRIBBLE, G. W. GRIBBLESearch for more papers by this authorT. C. BARDEN, T. C. BARDENSearch for more papers by this author G. W. GRIBBLE, G. W. GRIBBLESearch for more papers by this authorT. C. BARDEN, T. C. BARDENSearch for more papers by this author First published: July 29, 1986 https://doi.org/10.1002/chin.198630328Read the full textAboutPDF 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. Volume17, Issue30July 29, 1986 RelatedInformation

Syntheses of (+)-.alpha.- and (+)-.beta.-eudesmol and their diastereomers by intramolecular nitrone-olefin cycloaddition

Syntheses of (+)-.alpha.- and (+)-.beta.-eudesmol and their diastereomers by intramolecular nitrone-olefin cycloaddition

ChemInform Abstract: IRIDOIDS: THE TOTAL SYNTHESIS OF THE AGLUCONES OF (.+‐.)‐8‐EPILOGANIN AND (.+‐.)‐MUSSAENOSIDE VIA BICYCLO(3.3.0)OCTENES

AbstractDie Darstellung einer Reihe cis‐verknüpfter und unterschiedlich funktionalisierter Bicyclo[3.3.0]octane ‐ (III) bis (X) und (XIII) ‐ wird beschrieben.

Total syntheses of clavine alkaloids by an intramolecular nitrone-olefin cycloaddition reaction

The racemic ergot alkaloids chanoclavine I ( 1) and 6,7-secoagroclavine ( 4) have been synthesized stereoselectively from indole-4-carboxaldehyde ( 7) in overall yields of 14 and 13%, respectively. Further syntheses of isochanoclavine I ( 2), paliclavine ( 5) and costaclavine ( 6), via the same isoxazolidine 18 are described. The key step 16→ 18 (Scheme 4) involves a transient nitrone 17 which undergoes a kinetically controlled, regio- and stereoselective intramolecular cycloaddition to a 1,2-disubstituted olefinic bond.