1377848-08-2Relevant academic research and scientific papers
Aerobic Oxidation/Annulation Cascades through Synergistic Catalysis of RuCl3 and N-Heterocyclic Carbenes
Wang, Qian,Chen, Jiean,Huang, Yong
supporting information, p. 12806 - 12810 (2018/09/10)
Cooperative catalysis combining a transition metal with an N-heterocyclic carbene is challenging due to strong binding of NHCs towards 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. The resulting α,β-unsaturated acylazolium intermediate reacts selectively with 1,3-dicarbonyl compounds or ketones at either the β- or γ-carbon, yielding polysubstituted chiral lactones in high yield and with excellent enantioselectivity (up to 98 % yield, 94 % ee). This protocol can be applied to structurally sophisticated substrates.
Oxidative γ-addition of enals to trifluoromethyl ketones: Enantioselectivity control via lewis acid/n-heterocyclic carbene cooperative catalysis
Mo, Junming,Chen, Xingkuan,Chi, Yonggui Robin
, p. 8810 - 8813 (2012/07/02)
An oxidative γ-functionalization of enals under N-heterocyclic carbene (NHC) catalysis to give unsaturated δ-lactones is disclosed. Enantioselectivity control involving the relatively remote enal γ-carbon was achieved via Lewis acid [Sc(OTf)3 or combined Sc(OTf) 3/Mg(OTf)2] and NHC cooperative catalysis.
