A Convenient Synthesis of Tri- and Tetramethylbenzaldehydes from Readily Available Phenols
作者:Tom Sheppard、Persis Dhankher
DOI:10.1055/s-0033-1340302
日期:——
This letter describes a convenientsynthesis of the six isomeric tri- and tetramethylbenzaldehydes, which are not readily available from major chemical suppliers. Formylation of readily available phenols via electrophilic aromatic substitution provides compounds containing the correct aromatic substitution pattern. Suzuki cross-coupling of the corresponding trifluoromethanesulfonates with methylboronic
Enantiodivergent Atroposelective Synthesis of Chiral Biaryls by Asymmetric Transfer Hydrogenation: Chiral Phosphoric Acid Catalyzed Dynamic Kinetic Resolution
作者:Keiji Mori、Tsubasa Itakura、Takahiko Akiyama
DOI:10.1002/anie.201606063
日期:2016.9.12
enantiodivergent synthesis of chiral biaryls by a chiral phosphoric acid catalyzedasymmetrictransferhydrogenation reaction. Upon treatment of biaryl lactols with aromatic amines and a Hantzsch ester in the presence of chiral phosphoric acid, dynamic kinetic resolution (DKR) involving a reductive amination reaction proceeded smoothly to furnish both R and S isomers of chiral biaryls with excellent enantioselectivities