57081-00-2Relevant articles and documents
Palladium-Catalyzed Aerobic Oxidative Carbonylation of C–H Bonds in Phenols for the Synthesis of p-Hydroxybenzoates
Gaikwad, Vinayak V.,Bhanage, Bhalchandra M.
, p. 2877 - 2881 (2018/06/21)
This work reports the synthesis of p-hydroxybenzoates directly from phenols by oxidative carbonylation of phenolic C–H bonds, proceding through oxidative iodination. The developed methodology is efficient and economically attractive because phenols are cheap and easily available starting materials. This one-pot strategy was expediently applied to the synthesis of a variety of p-hydroxybenzoates by utilizing simple primary and secondary alcohols with different phenols under mild reaction conditions. Advantageously, the procedure has no need for co-catalysts, co-solvents or external ligands. The utilization of molecular oxygen as a terminal oxidant for C–H bond oxidation represents an additional benefit.
Aerobic oxidative heck/dehydrogenation reactions of cyclohexenones: Efficient access to meta-substituted phenols
Izawa, Yusuke,Zheng, Changwu,Stahl, Shannon S.
supporting information, p. 3672 - 3675 (2013/04/23)
Jockeying for the (meta)position: A new dicationic palladium(II) catalyst, employing a 6,6′-dimethyl-2,2′-bipyridine ligand, promotes both the aerobic oxidative Heck coupling and dehydrogenation reactions of cyclohexenones. These reactions may be combined in a one-pot sequence to enable the straightforward synthesis of meta-substituted phenols (see scheme). Copyright
Palladium-catalyzed aerobic dehydrogenation of substituted cyclohexanones to phenols
Izawa, Yusuke,Pun, Doris,Stahl, Shannon S.
scheme or table, p. 209 - 213 (2012/06/01)
Aromatic molecules are key constituents of many pharmaceuticals, electronic materials, and commodity plastics. The utility of these molecules directly reflects the identity and pattern of substituents on the aromatic ring. Here, we report a palladium(II) catalyst system, incorporating an unconventional ortho-dimethylaminopyridine ligand, for the conversion of substituted cyclohexanones to the corresponding phenols. The reaction proceeds via successive dehydrogenation of two saturated carbon-carbon bonds of the six-membered ring and uses molecular oxygen as the hydrogen acceptor. This reactivity demonstrates a versatile and efficient strategy for the synthesis of substituted aromatic molecules with fundamentally different selectivity constraints from the numerous known synthetic methods that rely on substitution of a preexisting aromatic ring.