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Updated: Feb 21, 2026

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Transformable Sulfoximine Assisted One-Pot Double Annulation of Vinylic C-H Bonds with Unactivated Alkynes
Majji Shankar1, Tirumaleswararao Guntreddi1, E Ramesh1
1School of Chemistry, University of Hyderabad , Hyderabad 500046, India.
Abstract:
The methylphenyl sulfoximine (MPS) directing group (DG) successfully promotes the one-pot double annulation of acrylic acids with alkynes under Ru catalysis, which is unprecedented. Diverse arrays of pyrido-fused-isoquinolinone skeletons are fabricated from acrylamides, creating two C-C and two C-N bonds in a single operation. The unsymmetrical annulation with two distinct alkynes is presented. The recovery of methylphenyl sulfoxide, a precursor of MPS, validates the synthetic adaptability of transformable-DG (TfDG) in C-H activation.
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