Gold-Catalyzed Synthesis of α-Fluoro Acetals and α-Fluoro Ketones from Alkynes
作者:Teresa de Haro、Cristina Nevado
DOI:10.1002/adsc.201000559
日期:2010.11.2
A new method to synthesize α-fluoroacetals and α-fluoroketones is presented here. In the presence of alcohols and Selectfluor, catalytic amounts of gold selectively transformed alkynes into the corresponding fluorinated acetals or ketones depending on the reaction conditions. This protocol has been applied to both terminal and internal alkynes showing a high degree of chemo- and regioselectivity
An efficient synthesis of spiroaminals over fused aminals has been successfully developed by bimetallic Au/Sc catalysis by using TMS as a traceless controlling group.
Catalytic activity of gold nanoclusters in intramolecular hydroamination of alkenes and alkynes with toluenesulfonamide under aerobic and basic conditions
作者:Hiroaki Kitahara、Hidehiro Sakurai
DOI:10.1016/j.jorganchem.2010.08.038
日期:2011.1
nanoclusters stabilized by a hydrophilic polymer, poly(N-vinyl-2-pyrrolidone) (Au:PVP), catalyzed the intramolecularhydroamination of toluenesulfonamides to unactivated alkenes/alkynes in EtOH under aerobic and basic conditions. The reaction proceeds via anti-addition of toluenesulfonamide to the alkenes assisted by π-activation of the gold clusters.
Free metal jacket: A regioselective metal‐free synthesis of polysubstitutedpyrroles has been developed through a (diacetoxyiodo)benzene‐mediated cascadereaction of alkynyl amines in moderate to good yield (see scheme).
Published as part of the Special Topic Modern Cyclization Strategies in Synthesis Abstract A transition-metal-free silane–iodine catalytic system comprising I2 and Et3SiH promotes intramolecular hydroalkoxylation/reduction and hydroamination/reduction of unactivated alkynes. This system allows the reaction to proceed at room temperature affording 2,4- and 2,5-disubstituted pyrrolidines as well as a