Atropisomerization in Confined Space; Cucurbiturils as Tools to Determine the Torsional Barrier of Substituted Biphenyls
作者:Roymon Joseph、Eric Masson
DOI:10.1002/ejoc.201301460
日期:2014.1
The torsional barrier of biphenyls bearing a prochiral dimethylsulfonium group at their 3-position could be determined by variable-temperature 1H NMR spectroscopy only after encapsulation into cucurbit[7]- or -[8]uril, which triggered the splitting of the two methyl signals. Confinement of the biphenyl units into the macrocycles amplifies the dissymmetry caused by the various ortho- and ortho′-substituents