Hexafluorobenzene: a powerful solvent for a noncovalent stereoselective organocatalytic Michael addition reaction
作者:Alessandra Lattanzi、Claudia De Fusco、Alessio Russo、Albert Poater、Luigi Cavallo
DOI:10.1039/c2cc17488j
日期:——
A dramatic enhancement of the diastereo- and enantioselectivity in the nitro-Michaeladdition reaction organocatalysed by a commercially available alpha,alpha-L-diaryl prolinol was disclosed when performing the reaction in unconventional hexafluorobenzene as a medium. DFT calculations were performed to clarify the origin of stereoselectivity and the role of C(6)F(6).
homodinuclear Co2/aminophenol sulfonamide complex has been developed for the asymmetric Michaelreaction of β-ketoesters with nitroolefins. This procedure is capable of tolerating a wide range of substrates and excellent results (up to 99% yield, >99 : 1 dr and 98% ee) can also be obtained. Moreover, the reaction could be carried out on a 50 mmol scale without any decrease in the enantioselectivity