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
Photoinduced Copper‐Catalyzed Coupling of Terminal Alkynes and Alkyl Iodides
作者:Avijit Hazra、Mitchell T. Lee、Justin F. Chiu、Gojko Lalic
DOI:10.1002/anie.201801085
日期:2018.5.4
We have developed a photoinduced copper‐catalyzed alkylation of terminal alkynes with primary, secondary, or tertiary alkyl iodides as electrophiles. The reaction has a broad substrate scope and can be successfully performed in the presence of ester, nitrile, aryl halide, ketone, sulfonamide, epoxide, alcohol, and amide functional groups. The alkylation is promoted by blue light (λ≈450 nm) and proceeds
Catalytic Anti-Markovnikov Hydroallylation of Terminal and Functionalized Internal Alkynes: Synthesis of Skipped Dienes and Trisubstituted Alkenes
作者:Melrose Mailig、Avijit Hazra、Megan K. Armstrong、Gojko Lalic
DOI:10.1021/jacs.7b02104
日期:2017.5.24
and functionalized internal alkynes. In this article, we describe the development of the reaction, exploration of the substrate scope, and a study of the reaction mechanism. Synthesis of skipped dienes through the hydroallylation of terminal alkyl and aryl alkynes with simple allyl phosphates and 2-substituted allyl phosphates is described. The hydroallylation of functionalized internal alkynes leads
Stereoselective Oxidative Bioconjugation of Amino Acids and Oligopeptides to Aldehydes
作者:Henriette N. Tobiesen、Lars A. Leth、Marc V. Iversen、Line Næsborg、Søren Bertelsen、Karl Anker Jørgensen
DOI:10.1002/anie.202008513
日期:2020.10.12
stereoselective, near‐equimolar, and metal‐free oxidative bioconjugation of amino acids and oligopeptides to aldehydes is presented. Based on a newly developed organocatalytic oxidative concept, the C‐terminal and side‐chain carboxylicacid functionalities of amino acids and oligopeptides are shown to couple in a stereoselective manner to α‐branched aldehydes catalyzed by a chiral primary amine and a quinone as
Cobalt-Catalyzed <i>Z</i>
-Selective Hydrosilylation of Terminal Alkynes
作者:Wei Jie Teo、Chao Wang、Ye Wei Tan、Shaozhong Ge
DOI:10.1002/anie.201700868
日期:2017.4.3
A cobalt‐catalyzed Z‐selective hydrosilylation of alkynes has been developed relying on catalysts generated from bench‐stable Co(OAc)2 and pyridine‐2,6‐diimine (PDI) ligands. A variety of functionalized aromatic and aliphatic alkynes undergo this transformation, yielding Z‐vinylsilanes in high yields with excellent selectivities (Z/E ratio ranges from 90:10 to >99:1). The addition of a catalytic amount