DOI: 10.1021/acs.orglett.6c04320 ISSN: 1523-7060
Stereodivergent Access to E - and Z -Vinylated Oxindoles via Pd-Catalyzed C(sp3)–H Activation/Heck Coupling, and Energy-Transfer Catalysis
Saleem Hafeez, Naveen Sihag, Dhanni, M Ramu YadavAbstract
A one-pot stereodivergent strategy for synthesizing E- and Z-vinylated oxindoles has been developed using a Pd-based tandem catalysis and Pd/Ir relay catalysis. The Pd(0)-catalyzed tandem sequence features a cyclization/C(sp3)–H activation/intermolecular Heck coupling to afford the E-isomer in high yields with excellent stereoselectivities. Integration of this transformation with an Ir-based energy-transfer process in a relay-catalytic mode enables access to the geometrically challenging Z-isomer. The broad substrate scope, late-stage functionalization of bioactive molecules, and synthetic derivatization highlight the method’s utility.