Gallium Tribromide Catalyzed Coupling Reaction of Alkenyl Ethers with Ketene Silyl Acetals
作者:Yoshihiro Nishimoto、Hiroki Ueda、Makoto Yasuda、Akio Baba
DOI:10.1002/anie.201203778
日期:2012.8.6
couple: The α‐alkenylation of esters was accomplished by GaBr3‐catalyzed coupling between alkenyl ethers and ketene silyl acetals. In this reaction system, various alkenyl ethers, including those with vinyl and substituted alkenyl groups, were applicable, and the scope of applicable ketene silyl acetals was sufficiently broad. The mechanism is also discussed.
The iodine‐catalyzed decarboxylative amidation of β,γ‐unsaturated carboxylic acids with chloramine salts is described. This method enables the regioselective synthesis of allylic amides from various types of β,γ‐unsaturated carboxylic acids containing substituents at the α‐ and β‐positions. In the reaction, N‐iodo‐N‐chloroamides, generated by the reaction of a chloramine salt with I2, function as a
Coupling Reaction of Enol Derivatives with Silyl Ketene Acetals Catalyzed by Gallium Trihalides
作者:Yoshihiro Nishimoto、Yuji Kita、Hiroki Ueda、Hiroto Imaoka、Kouji Chiba、Makoto Yasuda、Akio Baba
DOI:10.1002/chem.201602150
日期:2016.8.8
cross‐coupling reaction between enolderivatives and silyl ketene acetals catalyzed by GaBr3 took place to give the corresponding α‐alkenyl esters. GaBr3 showed the most effective catalytic ability, whereas other metal salts such as BF3⋅OEt2, AlCl3, PdCl2, and lanthanide triflates were not effective. Various types of enol ethers and vinyl carboxylates as enolderivatives are amenable to this coupling