Iron-Catalyzed α-Alkylation of Ketones with Secondary Alcohols: Access to β-Disubstituted Carbonyl Compounds
作者:Léo Bettoni、Sylvain Gaillard、Jean-Luc Renaud
DOI:10.1021/acs.orglett.0c00549
日期:2020.3.6
borrowing hydrogen strategy has been applied in the synthesis of β-branched carbonylcompounds. Various secondary benzylic and aliphatic alcohols have been used as alkylating reagents under mild reaction conditions. The ketones have been isolated in good to excellent yield. Deuterium labeling experiments provide evidence that the alcohol is the hydride source in this reaction and that no reversible step or
prevalent in biologically active compounds and in pharmaceuticals. A ruthenium-catalyzed direct synthesis of β-disubstituted ketones by cross-coupling of two different secondary alcohols is reported. This new protocol was applied to the synthesis of variety of β-disubstituted ketones from various cyclic, acyclic, symmetrical, and unsymmetrical secondary alcohols. An amine–amide metal–ligand cooperation
assimilating to provide the cross-coupled products. Reactions are sensitive to steric hindrance. This new C-C bond forming methodology requires low catalyst load and catalytic amount of base. Notably, the reaction produces H2 and H2O as the only byproducts making the protocol greener, atom economical and environmentally benign.
An assortment of aromatic ketones was successfully functionalized with a variety of unactivated secondary alcohols that serve as alkylating agents, providing β-disubstituted ketone products in good to excellent yields. Remarkably, challenging substrates such as simple acetophenone derivatives are effectively alkylated under this ruthenium catalysis. The substituted cyclohexanol compounds displayed
Nickel‐Catalysis Enabling α‐Alkylation of Ketones by Secondary Alcohols
作者:Amreen K Bains、Ayanangshu Biswas、Abhishek Kundu、Debashis Adhikari
DOI:10.1002/adsc.202200522
日期:2022.8.16
The α-alkylation of ketones utilizing a secondary alcohol has been accomplished by an isolable, bench-stable, inexpensive nickel catalyst affording high yields of β,β-disubstituted products. This report contributes a nickel catalyst in the pool of a few scarce examples of base metal discovered for this purpose. The substrate scope can span a wide range including aliphatic, alicyclic, and cyclic secondary