Palladium-Catalyzed Cascade Reactions of 1-(3-Arylprop-2-ynyloxy)-2-bromo Benzene Derivatives with Organoboron Compounds

Abstract

Applications of the cascade cyclocarbopalladation reaction followed by Suzuki-Miyaura coupling reactions of the readily available aryl-substituted propargylic aryl ethers with arylboronic acid and potassium trans-β-styryltrifluoroborate accomplish a new versatile entry in the synthesis of benzofuran derivatives. Notably, a new approach to the challenging synthesis of C3 functionalized 2-unsubstituted benzofurans has been developed by a cyclocarbopalladation/cross-coupling/aromatization process.

Fe(OTf)3‐Catalyzed Aromatization of Substituted 3‐Methyleneindoline and Benzo­furan Derivatives: A Selective Route to C‐3‐Alkylated Indoles and Benzofurans

“…Finally, we also tested this isomerization with stoichiometric amounts of bases such as K 3 PO 4 in DMF at 100 °C (Table 1, entry 10). Although, this strategy has been reported for the synthesis of 3‐substituted benzofuran derivatives,15 it did not work for the synthesis of indole derivative 3a . These results demonstrated that Fe(OTf) 3 has higher catalytic activity for this transformation.…”

Synthesis of aromatic functionalized cage-rearranged silsesquioxanes (T8, T10, and T12) via nucleophilic substitution reactions

“…Aromatic compounds play important roles as intermediates in organic synthesis, as the reactive functional groups (e.g. nitro, 1 aldehyde, 2 and bromo 3 ) on aromatic rings have been widely utilized for over a century as key chemicals for the synthesis of explosives, 4 dyes, 5 pharmaceuticals, 6 and polymers. 7 Meanwhile, polyhedral oligomeric silsesquioxanes have been well recognized as useful nanosized building blocks in the synthesis of organic-inorganic hybrid materials due to their versatile structure consisting of an inorganic Si-O-Si core and peripheral organic functional groups.…”

Advances in Palladium‐Catalyzed Cascade Cyclizations

“…As imilar strategyw as employed af ew years earlier by Arcadi et al in the synthesis of 3-ylidene-dihydro- benzofurans 26 from 2-aryl propargyl ethers 25 (Scheme 6). [16] Thea uthors propose a5 -exo-dig carbopalladation at the alkyne,f ollowed by the Suzuki coupling of the arylboronic acid. Va riation on R 1 was limited as was Ar 1 ,w hile both para and meta substituents on the arylboronic acid were tolerated.…”