Gold(I)-Catalyzed Intermolecular Dimerization of Internal Alkynes: Access to Bis-Indolic trans-Fused Pentacycles with
César R Solorio-Alvarado1, Narendra Mali1, Pedro Navarro-Santos2
1Universidad de Guanajuato, Campus Guanajuato, División de Ciencias Naturales y Exactas, Departamento de Química, Noria Alta S/N, 36050 Guanajuato, Guanajuato, Mexico.
Abstract:
Intermolecular gold(I)-catalyzed dimerization of internal alkynes remains a significant challenge. Herein, we report an efficient and mild gold(I)-catalyzed domino process that converts internal 1,3-diynoanilines into structurally complex bis-indolic trans-fused pentacyclic frameworks featuring a central seven-membered ring. This transformation forges three C-C bonds and constructs a five-ring molecule in a single operation. Mechanistic investigations, including DFT calculations, elucidate the key intermediates that govern this process.
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