The first diastereoselectivesynthesis of β-amino ketone and β-amino acid derivatives by palladium-catalyzed conjugate addition of arylboronic acids to chiral β-enamino ketones and β-enamino esters is reported. The catalytic system employing (S)-4-(tert-butyl)oxazolidin-2-one as the chiral auxiliary in water under an air atmosphere provides β-amino ketone and β-amino acid derivatives in high yields
Chain propagation determines the chemo- and regioselectivity of alkyl radical additions to C–O <i>vs.</i> C–C double bonds
作者:Tiffany O. Paulisch、Felix Strieth-Kalthoff、Christian Henkel、Lena Pitzer、Dirk M. Guldi、Frank Glorius
DOI:10.1039/c9sc04846d
日期:——
Investigations into the selectivity of intermolecular alkyl radical additions to C–O- vs. C–C-double bonds in α,β-unsaturated carbonyl compounds are described. Therefore, a photoredox-initiatedradical chain reaction is explored, where the activation of the carbonyl-group through an in situ generated Lewis acid – originating from the substrate – enables the formation of either C–O or the C–C-addition
Iridium-Catalyzed Synthesis of Substituted Indanones from Aromatic Carboxylates and Unsaturated Ketones
作者:Guodong Zhang、Zhiyong Hu、Giulia Bertoli、Lukas J. Gooßen
DOI:10.1021/acscatal.9b02536
日期:2019.9.6
A catalytic annulation is presented that provides straightforward, modular synthetic access to 3-substituted indanones from benzoic acids and α,β-unsaturated ketones. It is catalyzed by a bimetallic Ir/In system and proceeds via hydroarylation followed by Claisen condensation and optional retro-Claisen deacylation. The annulation may be combined into a one-pot procedure with the synthesis of the unsaturated
A Rh(III)-catalyzed enaminone-directed alkenyl C–H coupling with alkynes for the synthesis of salicylaldehyde derivatives is reported. This represents a unique example of benzene ring framework formation through a transition-metal-catalyzed, directed C–Hactivation strategy. The two incorporated reactive functionalities, aldehyde and hydroxy groups, provide convenient synthetic handles for further
secondary amine amide catalysts were developed for the asymmetric Michaeladdition of 4-hydroxycoumarin to α,β-unsaturated ketones. A series of important biologically and pharmaceutically active compounds were obtained in excellent yields (up to 99 %) with high enantioselectivities (up to 89 % ee) under mild conditions. In addition, enantiopure product could be obtained by a single recrystallization