title: Efficient Coupling Reaction of Quinone Monoacetal with Phenols Leading to Phenol Biaryls.
abstract: A simple and efficient synthesis of phenol biaryls by the cross-couplings of quinone monoacetals (QMAs) and phenols is reported. The Brønsted acid catalytic system in 1,1,1,3,3,3-hexafluoro-2-propanol was found to be particularly efficient for this transformation. This reaction can be extended to the synthesis of various phenol biaryls, including sterically hindered biaryls, with yields ranging from 58 to 90 % under mild reaction conditions and in a highly regiospecific manner.
authors.affiliation: Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Kamitanaka
authors.affiliation: College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Morimoto
authors.affiliation: College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Tsuboshima
authors.affiliation: College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Daichi
authors.initials: D
authors.lastname: Koseki
authors.affiliation: College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Hitoho
authors.initials: H
authors.lastname: Takamuro
authors.affiliation: College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Dohi
authors.affiliation: Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Kita
keywords: Brønsted acid; biaryls; cross-coupling; phenols; reaction mechanisms