beta-nitrostyrene has been researched along with squaric-acid* in 1 studies
1 other study(ies) available for beta-nitrostyrene and squaric-acid
Article | Year |
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Chiral squaramide derivatives are excellent hydrogen bond donor catalysts.
Thioureas represent the dominant platform for hydrogen bond promoted asymmetric catalysts. A large number of reactions, reported in scores of publications, have been successfully promoted by chiral thioureas. The present paper reports the use of squaramides as a highly effective new scaffold for the development of chiral hydrogen bond donor catalysts. Squaramide catalysts are very simple to prepare. The (-)-cinchonine modified squaramide (5), easily prepared through a two-step process from methyl squarate, was shown to be an effective catalyst, even at catalyst loadings as low as 0.1 mol%, for the conjugate addition reactions of 1,3-dicarbonyl compounds to beta-nitrostyrenes. The addition products were obtained in high yields and excellent enantioselectivities. Topics: Amides; Catalysis; Cinchona Alkaloids; Cyclobutanes; Hydrogen Bonding; Ketones; Nitro Compounds; Pentanes; Styrenes | 2008 |