A Regioselective Ruthenium‐Catalyzed Oxidative C–H Alkenylation of 2‐Aryl‐<i>4H</i>‐Benzo[<i>d</i>][<i>1</i>,<i>3</i>] Oxazin‐4‐Ones

ABSTRACT 2‐Aryl‐ 4H ‐benzo[ d ][ 1 , 3 ]oxazin‐ 4 ‐one derivatives can be directly alkenylated with alkyl acrylates using a facile Ru (II)‐catalyzed process; using Cu (OAc) 2 •H 2 O as an oxidizer through formation of a pentagon cyclic complex of imine‐Ru (II) for C–H activation is described. The unique catalytic reaction is well matched with miscellaneous olefins such as vinyl ketones, acrylonitrile, and acrylates. The aryl rings bearing electronically diverse substituents tolerated the reaction conditions to provide ortho‐alkenylation products in high regioselectivities and admissible yields.