62338-03-8Relevant articles and documents
Organophotoredox-Catalyzed Three-Component Coupling of Heteroatom Nucleophiles, Alkenes, and Aliphatic Redox Active Esters
Shibutani, Shotaro,Nagao, Kazunori,Ohmiya, Hirohisa
supporting information, p. 1798 - 1803 (2021/03/03)
This manuscript describes a visible-light-mediated organophotoredox catalytic process for vicinal difunctionalization of alkenes using heteroatom nucleophiles and aliphatic redox active esters. A wide range of heteroatom nucleophiles including alcohols, water, carboxylic acids, amides, and halogens can be used for this reaction. This radical relay type reaction allows forging of C(sp3)-C(sp3) with a carbon-centered radical and C(sp3)-heteroatom bonds with a benzyl cation on the vinylarenes with complete regioselectivity in a single step.
Reductive Lithiation in the Absence of Aromatic Electron Carriers. A Steric Effect Manifested on the Surface of Lithium Metal Leads to a Difference in Relative Reactivity Depending on Whether the Aromatic Electron Carrier Is Present or Absent
Kennedy, Nicole,Lu, Gang,Liu, Peng,Cohen, Theodore
, p. 8571 - 8582 (2015/09/15)
One of the most widely used methods of preparation of organolithium compounds is by the reductive lithiation of alkyl phenyl thioethers or, usually less conveniently, alkyl halides with either aromatic radical-anions of lithium or lithium metal in the presence of an aromatic electron-transfer catalyst. Here we present results showing that lithium dispersion can achieve reductive lithiation in the absence of the electron-transfer agent. This procedure is more efficient, and surprisingly, the order of reactivity of substrates is reversed depending on whether the electron-transfer agent is present or absent. For example, in the presence of a preformed radical-anion, tert-butyl phenyl sulfide cleaves significantly faster than methyl phenyl sulfide, whereas in the absence of the radical-anion, it is just the opposite. Density functional theory calculations reveal that the exothermicity of the cleavage of the C-S bond in alkyl phenyl thioethers on the lithium surface is dependent on the size of the alkyl group, the smaller the alkyl group the greater the exothermicity. The increased reactivity is attributed to the smaller steric repulsion between the alkyl group and the lithium surface. The methodology includes, but may not be limited to, the lithium dispersion reductive lithiation of phenyl thioethers, alkyl chlorides, acrolein diethyl acetal, and isochroman.
Chiral secondary alcohol-induced asymmetric autocatalysis: correlation between the absolute configuration of the chiral initiators and the product
Shibata, Takanori,Iwahashi, Kimiko,Kawasaki, Tsuneomi,Soai, Kenso
, p. 1759 - 1762 (2008/02/11)
In the presence of various chiral secondary alcohols as chiral initiators, an enantioselective alkylation of a pyrimidine-5-carbaldehyde using diisopropylzinc was examined: a pyrimidyl alkanol was obtained in high yield and enantiomeric excess. The correl
