The Direct Asymmetric Vinylogous Aldol Reaction of Furanones with α-Ketoesters: Access to Chiral γ-Butenolides and Glycerol Derivatives
作者:Jie Luo、Haifei Wang、Xiao Han、Li-Wen Xu、Jacek Kwiatkowski、Kuo-Wei Huang、Yixin Lu
DOI:10.1002/anie.201006316
日期:2011.2.18
Twice as good: The title reaction using the tryptophan‐derived bifunctional organic catalyst 1 has been developed. The reported method led to the synthesis of chiral γ‐substituted butenolides in excellent yields, with high diastereo‐ and enantioselectivities. Facile synthesis of chiralglycerolderivatives containing a tertiary hydroxy group has also been demonstrated.
N-Heterocyclic Carbene-Catalyzed Vinylogous Mukaiyama Aldol Reaction of α-Keto Esters and α-Trifluoromethyl Ketones
作者:Guang-Fen Du、Ying Wang、Fen Xing、Mei Xue、Xu-Hong Guo、Kuo-Wei Huang、Bin Dai
DOI:10.1055/s-0035-1560833
日期:——
N-Heterocyclic carbene (NHC)-catalyzed vinylogous Mukaiyama aldol reaction of ketones was developed. Under the catalysis of 5 mol% NHC, -keto esters and -trifluoromethyl ketones reacted with 2-(trimethysilyloxy)furan efficiently to produce -substituted butenolides containing adjacent quaternary and tertiary carbon centers in high yields with good diastereoselectivities.
A Simple Tetraminocalix[4]arene as a Highly Efficient Catalyst under “On-Water” Conditions through Hydrophobic Amplification of Weak Hydrogen Bonds
作者:Margherita De Rosa、Pellegrino La Manna、Annunziata Soriente、Carmine Gaeta、Carmen Talotta、Neal Hickey、Silvano Geremia、Placido Neri
DOI:10.1002/chem.201701247
日期:2017.5.23
simple tetraminocalix[4]arene 1, which contains weak H‐bond‐donor NH2 groups, is reported to be a highly efficient organocatalyst for the Vinylogous Mukaiyama Aldol Reaction (VMAR) of 2‐(trimethylsilyloxy)furan 5 with α‐ketoesters 6 a–l under “on‐water” conditions owing to the hydrophobic amplification of weak H‐bond interactions. The catalytic efficiency of calixarene catalyst 1 was shown to be closely