N-Heterocyclic Carbene-Catalyzed α,β-Unsaturated Aldehydes Umpolung in Fullerene Chemistry: Construction of [60]Fullerene-Fused Cyclopentan-1-ones and Cyclohex-2-en-1-ones
first umpolung strategy for the cycloacylation of fullerene using a N-heterocyclic carbene organocatalyst is reported. The coupling of [60]fullerene with different structural α,β-unsaturated aldehydes efficiently furnishes interesting [60]fullerene-fused cyclopentan-1-ones or cyclohex-2-en-1-ones in good to excellent yields. This newreaction displays a wide substrate scope and excellent functional-group
Aerobic Oxidation/Annulation Cascades through Synergistic Catalysis of RuCl<sub>3</sub>
and N-Heterocyclic Carbenes
作者:Qian Wang、Jiean Chen、Yong Huang
DOI:10.1002/chem.201803254
日期:2018.9.3
Cooperative catalysis combining a transition metal with an N‐heterocyclic carbene is challenging due to strong binding of NHCstowards late transition metals. We report the first example of synergistic catalysis by a chiral NHC and a coordinatively unsaturated ruthenium compound. RuCl3 was found to mediate efficient aerobic oxidation of homoenolates generated from enals and the N‐heterocyclic carbene
A novel N-heterocyclic carbene-catalyzed three-component umpolung hydroalkylation of [60]fullerene with 4-(chloromethyl)-benzaldehydes/α,β-unsaturatedaldehydes and alcohols/thioalcohols has been developed for the flexible and efficientpreparation of diverse monoalkylated hydrofullerenes. Organic catalysis, broad substrate scope, excellent functional group tolerance, and products with high diversity