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Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Phosphine-Promoted Synthesis of Naphthoquinones Fused with Cyclopentadienyl Moiety Via Ring Expansion: Synthesis,
Wei-Qing Wang1, Sureshbabu Nallapati1, Chun-Yu Chen1
1Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan.
Abstract:
Phosphine-promoted unprecedented [3 + 2] annulation reactions via ring expansion by using 2-benzylidene-indane-1,3-diones and diynoates for the synthesis of biologically interesting novel naphthoquinones fused with a five-membered ring bearing a phosphorus ylide up to 78% yield are described. Further ring contraction through [1,5] sigmatropic rearrangement to the spiro indan-1,3-diones by mCPBA oxidation was revealed and inferred through oxidation, followed by protonation. The relevant structures were confirmed by single-crystal X-ray diffraction. Electrochemical studies show that the naphthoquinones and lactones with phosphorus ylides could be applied to redox colorimetric materials.
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