Wei Zhuang, Thomas B. Poulsen and Karl Anker Jørgensen
Org. Biomol. Chem., 2005,3, 3284-3289
DOI:
10.1039/B507778H,
Paper
Bis-sulfonamides are demonstrated to be promising candidates for the efficient activation of carbonyl compounds through hydrogen bonding. Exemplified by three carbonyl addition reactions: Mukaiyama-aldol, hetero Diels–Alder and Friedel–Crafts reactions we show that bis-triflamides or bis-nonaflamides of commercially available chiral diamines act as chiral Brønsted-acid catalysts, leading to the optically active products in moderate to excellent yields and with enantioselectivities up to 73% ee.