Ligand-Controlled Chemoselective C(acyl)–O Bond vs C(aryl)–C Bond Activation of Aromatic Esters in Nickel Catalyzed C(sp<sup>2</sup>)–C(sp<sup>3</sup>) Cross-Couplings
converted into the alkylated arenes and ketone products, respectively. The utility of this newly developed protocol was demonstrated by its wide substrate scope, broad functional group tolerance and application in the synthesis of keyintermediates for the synthesis of bioactive compounds. DFT studies on the oxidative addition step helped rationalizing this intriguing reaction chemoselectivity: whereas
Switchable Selectivity in the Pd-Catalyzed Alkylative Cross-Coupling of Esters
作者:Jeanne Masson-Makdissi、Jaya Kishore Vandavasi、Stephen G. Newman
DOI:10.1021/acs.orglett.8b01646
日期:2018.7.6
The Pd-catalyzed cross-coupling of phenyl esters and alkyl boranes is disclosed. Two reaction modes are rendered accessible in a selective fashion by interchange of the catalyst. With a Pd–NHC system, alkyl ketones can be prepared in good yields via a Suzuki–Miyaurareaction proceeding by activation of the C(acyl)–O bond. Use of a Pd–dcype catalyst enables alkylated arenes to be synthesized by a modified
Synthesis of Isomerically Pure (<i>Z</i>)-Alkenes from Terminal Alkynes and Terminal Alkenes: Silver-Catalyzed Hydroalkylation of Alkynes
作者:Mitchell T. Lee、Madison B. Goodstein、Gojko Lalic
DOI:10.1021/jacs.9b09336
日期:2019.10.30
molecules and often are used as intermediates in organic synthesis. Many alkenes exist in two stereoisomeric forms (E and Z), which have different structures and different properties. The selective formation of the two isomers is an important synthetic goal that has long inspired the development of new synthetic methods. However, the efficient synthesis of diastereopure, thermodynamically less stable, Z-alkenes
Expanding the substitution pattern of 2(1H)-pyrazinones via Suzuki and Heck reactions
作者:Rasha Azzam、Wim M. De Borggraeve、Frans Compernolle、Georges J. Hoornaert
DOI:10.1016/j.tet.2005.02.056
日期:2005.4
Various 3,5-dichloropyrazinones were substituted at the C-3 position with (hetero)aryl, alkyl and alkenyl groups by means of Suzuki and Heck reactions. The methodology could be extended to reactions on the far less reactive C-5 position by transhalogenation of the 5-Cl substituent to a 5-Br or a 5-I group prior to performing the cross-coupling. (c) 2005 Elsevier Ltd. All rights reserved.
Hydroboration. 56. Convenient and regiospecific route to functionalized organosilanes through the hydroboration of alkenylsilanes