Enantioselective organocatalytic Michael addition of malonates to α,β-unsaturated aldehydes in water
作者:Anqi Ma、Shaolin Zhu、Dawei Ma
DOI:10.1016/j.tetlet.2008.03.051
日期:2008.5
The Michaeladdition of malonates to α,β-unsaturated aldehydes catalyzed by O-TMS protected diphenylprolinols and acetic acid in water occurs at 0 °C to rt. In most cases, the reaction runs to completion in less than 24 h. A wide range of aldehydes including β-aryl, β-alkyl and β-alkenyl acroleins are found to be compatible with these conditions, providing the corresponding adducts in good yields and
A Recyclable Chiral 2‐(Triphenylmethyl)pyrrolidine Organocatalyst Anchored to [60]Fullerene
作者:Cristian Rosso、Marco G. Emma、Ada Martinelli、Marco Lombardo、Arianna Quintavalla、Claudio Trombini、Zois Syrgiannis、Maurizio Prato
DOI:10.1002/adsc.201900009
日期:2019.6.18
[60]fullerene via click chemistry provides a highlyefficient supported enantioselectiveorganocatalyst, which was successfully exploited in a Michaeladdition of malonates to cinnamaldehydes, via iminium ion activation. The supported organocatalyst was recycled up to six times, with only a moderate decrease in terms of activity and with no loss in enantioselectivity.
carboxylation/halogenation, and next lactonization of γ,γ-dicarbonyl-substituted aldehydes has been realized using an eco-friendly, safe and inexpensive solid sodiumchlorite (NaClO2)/1,3-dibromo-5,5-dimethyl-hydantoin (DBDMH) combination. This new reaction is amenable to a multi-gram scale-up with high yield.
An enantio- and diastereoselective approach to indoloquinolizidines in continuous flow
作者:Moreshwar B. Chaudhari、Prachi Gupta、Patricia Llanes、Leijie Zhou、Nicola Zanda、Miquel A. Pericàs
DOI:10.1039/d2ob01462a
日期:——
short synthesis of indoloquinolizidines. Using this approach, a highly enantioselective, solvent-free and rapid conjugate addition of dimethyl malonate to a diverse family of cinnamaldehydes in continuous flow, allowing the preparation of relevant oxodiesters in multigram amounts has been developed. The obtained Michael adducts have been used to complete an expedient diastereoselective synthesis of indoloquinolizidine