In situ mechanochemical synthesis of nitrones followed by 1, 3-dipolar cycloaddition: a catalyst-free, "green" route to cis-fused chromano[4, 3-c]isoxazoles. Issue 120 (20th November 2015)

• Record Type: Journal Article
• Authors: Bhutia, Zigmee T.; P., Geethika; Malik, Anurag; Kumar, Vikash; Chatterjee, Amrita; Roy, Biswajit Gopal; Banerjee, Mainak
• Is Part Of: RSC advances. Volume 5:Issue 120(2015)
• Page Start: 99566
• Page End: 99572
• Publication Date: 2015-11-20
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c5ra21044e
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : An efficient, catalyst free mechanochemical route to cis -fused chromano[4, 3- c ]isoxazoles has been developed via a simple mortar-pestle grinding method. Abstract : An efficient and catalyst-free method for the synthesis of cis -fused chromano[4, 3- c ]isoxazoles via intramolecular 1, 3-dipolar nitrone cycloaddition involving hand-grinding in a mortar-pestle has been developed. The mechanochemical agitation was sufficient for dehydrative nitrone formation by condensation of various O -allyl salicylaldehyde derivatives and alkyl/aryl hydroxylamines. The corresponding nitrones undergo intramolecular 1, 3-dipolar cycloaddition leading to regioselective formation of cis -fused tetrahydrochromeno[4, 3- c ]isoxazole derivatives in high yields. The key features of this new method are cleaner reaction profiles, catalyst-free conditions, high yields, and short reaction times.