Cinchona-based squaramide-catalysed cascade aza-Michael–Michael addition: enantioselective construction of functionalized spirooxindole tetrahydroquinolines
作者:Wen Yang、Da-Ming Du
DOI:10.1039/c3cc44930k
日期:——
An efficient enantioselective cascadeaza-Michael-Michael addition reaction catalysed by a chiral bifunctional tertiary amine-squaramide catalyst has been developed. This cascadereaction proceeded well under mild conditions, furnishing highly functionalized spirooxindole tetrahydroquinolines with three contiguous stereocenters in excellent yields with excellent diastereoselectivities (>25:1 dr) and
An unprecedented organocatalyzed aerobic oxidative Robinson annulation of 2-isocyanochalcones with active methylene ketones was developed for the expedientsynthesis of phenanthridines and hydrophenanthridinones in high to excellent yields.
Redox-Neutral Access to Sultams from 2-Nitrochalcones and Sulfur with Complete Atom Economy
作者:Thanh Binh Nguyen、Pascal Retailleau
DOI:10.1021/acs.orglett.7b01766
日期:2017.7.21
A catalyst-free, redox-neutral, and completely atom-economical synthesis of sultams by simply heating 2-nitrochalcones with elemental sulfur in 3-picoline or N-methylmorpholine is described. The S–N, C–S, and S═O bonds of the sulfonamide are efficiently formed between the nitrogen atom of the 2-nitro group and the α-carbon of the chalcones and elemental sulfur with the migration of two oxygen atoms
synthesis of chiral tetrahydroquinoline derivatives with excellent enantioselectivities and high yields has been developed through one‐pot cascade biomimetic reduction. The detailed reaction pathway includes the acid‐catalyzed and ruthenium‐catalyzedformation of aromatic quinoline intermediates and biomimetic asymmetric reduction.
Syntheses of 4-Indolylquinoline Derivatives via Reductive Cyclization of Indolylnitrochalcone Derivatives by Fe/HCl
作者:Wen-Chang Chen、Chan-Chieh Lin、Veerababurao Kavala、Chun-Wei Kuo、Chia-Yu Huang、Ching-Fa Yao
DOI:10.3390/molecules201219862
日期:——
procedure for the synthesis of 4-indolylquinoline derivatives is described. This process involves two steps, the first of which is the Michael addition of indole to nitrochalcones promoted by sulfamic acid under solvent free conditions and the second step is a reductive cyclization of the indolylnitrochalcone intermediates to 4-indolylquinoline derivatives by Fe/HCl in ethanol. In both steps, the reactions