TfOH catalysed domino-double annulation of arenes with propargylic alcohols: a unified approach to indene polycyclic systems

• Published in: Chemical communications (Cambridge, England) Vol. 57; no. 95; pp. 12796 - 12799
• Main Authors: Baire, Beeraiah, Yadav, Bhavna
• Format: Journal Article
• Language: English
• Published: CAMBRIDGE Royal Soc Chemistry 30.11.2021; Royal Society of Chemistry
• Subjects: Alcohols; Aromatic compounds; Chemical reactions; Chemistry; Chemistry, Multidisciplinary; Covalent bonds; Dehydration; Indene; Organic chemistry; Physical Sciences; Science & Technology; MEYER-SCHUSTER REARRANGEMENT; GOLD; ROUTE; ETHERS; INTRAMOLECULAR HYDROARYLATION; COUPLING REACTIONS; INDANYL CATIONS; CYCLIZATION
• ISSN: 1359-7345; 1364-548X
• DOI: 10.1039/d1cc05253e

The design and development of a TfOH catalysed domino strategy for the double annulation of arenes with propargylic alcohols for the rapid generation of indene based polycyclic systems is reported. The dehydration, intramolecular 6-endo-dig hydroarylation, and cationic cyclization were consecutively promoted by TfOH. The key features of this strategy are the formation of two C-C bonds, unified access to indene polycyclic systems, excellent yields (up to 95%), high atom economy (>90%), an operationally simple procedure, and water being the only byproduct. By extending this strategy, a two-step synthesis of the pentacyclic systems of hypoxylonol A (43% overall yield from α-tetralone), daldinone A (63% overall yield from β-tetralone) and spiro-tetracyclic framework of incarviatone A has also been achieved. TfOH catalysed domino-double annulation of arenes with propargylic alcohols is developed for the generation of indene based polycyclic systems. Three distinct reactions, dehydration-intramolecular hydroarylation-cationic cyclization were promoted.