Homogeneous and Gas–Liquid Catellani‐Type Reaction Enabled by Continuous‐Flow Chemistry
作者:Alessandra Casnati、Hannes P. L. Gemoets、Elena Motti、Nicola Della Ca'、Timothy Noël
DOI:10.1002/chem.201803909
日期:2018.9.20
palladium‐catalyzed Catellani‐type reaction using a continuous‐flow platform is described. The implementation of continuous‐flow technology allowed the acceleration of the transformation and, for the first time, expansion of the chemical space to gaseous olefins (i.e., ethylene, propylene and 3,3,3‐trifluoropropene), thus providing a safe and practical approach to sterically hindered ortho‐disubstituted
Sequential Unsymmetrical Aryl Coupling of <i>o</i>-Substituted Aryl Iodides with <i>o</i>-Bromophenols and Reaction with Olefins: Palladium-Catalyzed Synthesis of 6<i>H</i>-Dibenzopyran Derivatives
Dibenzopyran derivatives are prepared by palladium- and norbornene-catalyzed reaction of aryliodides, o-substituted with electron-releasing substituents, o-bromophenols, and activated alkenes.
In the presence of Pd(OAc) 2 and norbornene as catalysts, ortho-substituted aryl iodides and terminal olefins react to afford selectively substituted ortho-vinylbiphenyl derivatives in good yields. The reaction proceeds through a series of steps including norbornene insertion and C-H activation with formation of pallada-cycles able to promote arylation of their aromatic part. Norbornene deinsertion