Enantioselective Construction of Quaternary Stereogenic Centers by the Addition of an Acyl Anion Equivalent to 1,3-Dienes
作者:Nathan J. Adamson、Sangjune Park、Pengfei Zhou、Andrew L. Nguyen、Steven J. Malcolmson
DOI:10.1021/acs.orglett.0c00412
日期:2020.3.6
We report the enantioselective formation of quaternary stereogenic centers by the intermolecular addition of malononitrile, an acyl anion equivalent, and related pronucleophiles to several 1,3-disubstituted acyclic 1,3-dienes in the presence of a Pd-PHOX catalyst. Products are obtained in up to 88% yield and 99:1 er and in most cases are formed as a single regioisomer. The products' malononitrile unit
Benzylamine as Hydrogen Transfer Agent: Cobalt‐Catalyzed Chemoselective C=C Bond Reduction of β‐Trifluoromethylated α,β‐Unsaturated Ketones via 1,5‐Hydrogen Transfer
of β-CF3 -α,β-unsaturatedketones using benzylamine as hydrogen transfer agent involving intramolecular 1,5-hydrogen transfer is reported. The reaction proceeded smoothly with a relatively wide range of substrates including those bearing aromatic heterocycles such as a furyl ring system in high yields (74-92 %). This provides an efficient method for the synthesis of β-CF3 saturated ketones in one-pot
A Copper-Catalyzed Reductive Defluorination of β-Trifluoromethylated Enones via Oxidative Homocoupling of Grignard Reagents
作者:Xiaoting Wu、Fang Xie、Ilya D. Gridnev、Wanbin Zhang
DOI:10.1021/acs.orglett.8b00379
日期:2018.3.16
An efficient copper-catalyzed reductive defluorination of β-trifluoromethylated enones via an oxidative homocoupling of Grignard reagents is reported. The reaction proceeded smoothly with a wide range of substrates, including the ones bearing aromatic heterocycles, such as furyl and thienyl ring systems in high yields (80–92%, except one example) under mild conditions. This provides a practical method