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Updated: Jan 14, 2026

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
One-Pot Assembly of Dihydrofluoren-3-ones via Intramolecular Annulation of Alkynyl-Alkynones: A Way to Functionalized
Chada Raji Reddy1, Ankita Kumari1, Adla Vijender1
1Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India.
Abstract:
Herein, we reveal an approach for the synthesis of a unique structural framework, dihydrofluoren-3-one, from the reaction of propargylic alcohol with alkynyl silyl enol ether. The transformation proceeds through acid-catalyzed propargylation of silyl enol ether leading to alkynyl-alkynones and subsequent intramolecular annulation (3+2 cycloaddition) in the presence of PPh3AuNTf2 (2 mol %). This novel dihydrofluoren-3-one motif was found to be a versatile precursor to provide diverse functionalized fluorenes.
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