Regioselective Diboron-Mediated Semireduction of Terminal Allenes
作者:Ashley M. Gates、Webster L. Santos
DOI:10.1055/s-0039-1690207
日期:2019.12
A method for the regioselective reduction of the terminaldoublebond of 1,1-disubstituted allenes has been developed. In the presence of a palladium catalyst, tetrahydroxydiboron and stoichiometric water, allene semireduction proceeds in high yield to afford Z-alkenes selectively.
Titanocene(III)‐Catalyzed Precision Deuteration of Epoxides
作者:Dina Schwarz G. Henriques、Elena Rojo‐Wiechel、Sven Klare、Regine Mika、Sebastian Höthker、Jonathan H. Schacht、Niklas Schmickler、Andreas Gansäuer
DOI:10.1002/anie.202114198
日期:2022.2
Titanocene catalysis delivers D to the more substituted C-atom of epoxides with high efficiency, deuterium incorporation, and stereoselectivity. A novel method of catalyst activation that prevents isotope scrambling warrants the excellent performance of the reaction.
二茂钛催化将 D 传递至环氧化物中取代较多的 C 原子,具有高效率、氘并入和立体选择性。一种防止同位素扰乱的催化剂活化新方法保证了反应的优异性能。
Cobalt-Catalyzed Migrational Isomerization of Styrenes
作者:Jiajin Zhao、Biao Cheng、Chenhui Chen、Zhan Lu
DOI:10.1021/acs.orglett.9b04305
日期:2020.2.7
An efficient cobalt-catalyzed migrational isomerization of styrenes was developed using the thiazoline iminopyridine (TIP) ligand. This reaction is operationally simple and atom economical using readily available starting materials to access trisubstituted alkenes. Even when using a 0.1 mol % catalyst loading, the reaction could be conducted in neat and completed in 1 h with excellent conversion and high E stereoselectivity.
E- and Z-, di- and tri-substituted alkenyl nitriles through catalytic cross-metathesis
作者:Yucheng Mu、Thach T. Nguyen、Ming Joo Koh、Richard R. Schrock、Amir H. Hoveyda
DOI:10.1038/s41557-019-0233-x
日期:2019.5
the development of several efficient catalytic cross-metathesis strategies, which provide direct access to a considerable range of Z- or E-di-substituted cyano-substituted alkenes or their corresponding tri-substituted variants. Depending on the reaction type, a molybdenum-based monoaryloxide pyrrolide or chloride (MAC) complex may be the optimal choice. The utility of the approach, enhanced by an easy
Iron Catalyzed Isomerization of
<scp>α‐Alkyl</scp>
Styrenes to Access Trisubstituted Alkenes
作者:Songgen Xu、Guixia Liu、Zheng Huang
DOI:10.1002/cjoc.202000492
日期:2021.3
supported by phosphine‐pyridine‐oxazoline (PPO) ligand. The protocol provides an atom‐efficient and operationally simple approach to trisubstituted alkenes in high yields with excellent regio‐ and stereoselectivities under mild conditions. The results of deuterium‐labelling and radical trap experiments are consistent with an iron‐hydride pathway involving reversible alkene insertion and β‐H elimination.