Enantioselective Allylation of Alkenyl Boronates Promotes a 1,2-Metalate Rearrangement with 1,3-Diastereocontrol
作者:Colton R. Davis、Irungu K. Luvaga、Joseph M. Ready
DOI:10.1021/jacs.1c01242
日期:2021.4.7
Alkenyl boronates add to Ir(π-allyl) intermediates with high enantioselectivity. A 1,2-metalate shift forms a second C–C bond and sets a 1,3-stereochemical relationship. The three-component coupling provides tertiary boronic esters that can undergo multiple additional functionalizations. An extension to trisubstituted olefins sets three contiguous stereocenters.
Iridium-Catalyzed Enantioselective Synthesis of α-Chiral Bicyclo[1.1.1]pentanes by 1,3-Difunctionalization of [1.1.1]Propellane
作者:Songjie Yu、Changcheng Jing、Adam Noble、Varinder K. Aggarwal
DOI:10.1021/acs.orglett.0c02017
日期:2020.7.17
3-difunctionalization of [1.1.1]propellane with Grignard reagents and allyl carbonates using iridium catalysis. This mild protocol proceeds via initial organometallic addition to [1.1.1]propellane followed by asymmetric allylic substitution, providing the products with high enantioselectivities over a broad range of substrates. Further derivatization of the products demonstrates the applicability of this method
Cobalt-Catalyzed Diastereo- and Enantioselective Reductive Allyl Additions to Aldehydes with Allylic Alcohol Derivatives via Allyl Radical Intermediates
enantioenriched homoallylic alcohols with a remarkably broad scope of allyl groups that can be introduced. Mechanistic studies indicated that allyl radical intermediates were involved in this process. These new discoveries establish a new strategy for development of enantioselective transformations through capture of radicals by chiral Co complexes, pushing forward the frontier of Co complexes for enantioselective
Direct Palladium-Catalyzed Intermolecular Allylation of Highly Electron-Deficient Polyfluoroarenes
作者:Shilu Fan、Fei Chen、Xingang Zhang
DOI:10.1002/anie.201008174
日期:2011.6.20
A simple operation: The use of readily available PPh3, high reaction efficiency, and good stereo‐ and regioselectivity provided useful and operationally simple access to polyfluoroarylated derivatives through the title transformation (see scheme; phen=1,10‐phenanthroline). The reaction mechanism was also studied.
nucleophile was developed. The reaction utilizes inexpensive and readily available (CH3CN)3W(CO)3 as a precatalyst and proceeds at 60 °C temperature in the presence of 2,2′-bipyridine and its derivatives as ligand. The synthetic utility of allylic sulfones as electrophile was further demonstrated through Suzuki–Miyaura cross-coupling as showcased by the formal synthesis of (±)-hinokiresinol.