A four-component reaction to access 3,3-disubstituted indolines via the palladium–norbornene-catalyzed ortho amination/ipso conjunctive coupling

Abstract

The development of a palladium/norbornene-catalyzed four-component reaction, involving ortho C–H amination/ipso conjunctive coupling with an alkene and an external nucleophile, is reported.

Catalytic ortho C–H methylation and trideuteromethylation of arylthianthrenium salts via the Catellani strategy

“…Since its discovery by Catellani in 1997, the Catellani reaction has been recognized as a potent method for the modular synthesis of highly substituted arenes. 11 In recent decades, Lautens, 12 Dong, 13 Zhou, 14 Liang, 15 and other researchers 16 have made significant advancements in this field, establishing this methodology as a reliable route for synthesizing complex arenes. In contrast to the diverse variations of nucleophilic and electrophilic reagents, the substrates used in Catellani-type reactions have been mainly confined to aryl halides (triflates), 11,17,18 aryl thioesters, 19 aryl diazonium salts, 20 aryl boronic acids, 21 vinyl halides (triflates), 22,23 indoles, 24 carbazoles, 25 thiophenes, 26 and arenes with directing groups, 27 and the exploitation of arylthianthrenium salts has remained elusive (Scheme 1d).…”

Chiral dinitrogen ligand enabled asymmetric Pd/norbornene cooperative catalysis toward the assembly of C–N axially chiral scaffolds

“…However, the latter, originated from the indirect stereocontrol mode of chiral NBE strategy (generating a C–C chiral axis before the release of chiral NBE, followed by chirality transferring C–N formation) 50 , could only be solved through tuning the chiral induction strategy. While chiral amine strategy developed by Zhou 46 and Gong 47 is specific for carbonyl coupling partners, the chiral ligand strategy pioneered by Gu 48 , 49 has only been applied to C–C formation involved asymmetric Catellani reactions in less satisfactory enantioselectivities 52 . In accordance with our continuous efforts on constructing C–N axially chiral scaffolds 12 , 26 , we intended to explore a practical asymmetric Catellani route toward such compounds complementary to chiral NBE strategy.…”