title: A domino palladium-catalyzed C-C and C-O bonds formation via dual O-H bond activation: synthesis of 6,6-dialkyl-6H-benzo[c]chromenes.
abstract: An efficient Pd-catalyzed domino reaction of α,α-dialkyl-(2-bromoaryl)methanols to 6,6-dialkyl-6H-benzo[c]chromenes is presented. Their formation can be explained via a five membered Pd(II)-cycle that efficiently involves a domino homocoupling with the second molecule, β-carbon cleavage, and finally intramolecular Buchwald-Hartwig cyclization. This domino process effectively involves breaking of five σ-bonds (2C-Br, 2O-H, and a C-C) and formation of two new σ-bonds (C-C and C-O). This mechanistic pathway is unprecedented and further illustrates the power of transition metal catalysis.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Hyderabad, Ordnance Factory Estate Campus, Yeddumailaram - 502 205, Medak District, Andhra Pradesh, India.
authors.forename: Lodi
authors.initials: L
authors.lastname: Mahendar
authors.forename: Jonnada
authors.initials: J
authors.lastname: Krishna
authors.forename: Alavala Gopi Krishna
authors.initials: AG
authors.lastname: Reddy
authors.forename: Bokka Venkat
authors.initials: BV
authors.lastname: Ramulu
authors.forename: Gedu
authors.initials: G
authors.lastname: Satyanarayana