Asymmetric organocatalytic anthrone additions to activated alkenes
作者:Alex Zea、Andrea-Nekane R. Alba、Natalia Bravo、Albert Moyano、Ramon Rios
DOI:10.1016/j.tet.2011.02.032
日期:2011.4
Asymmetric organocatalyticadditions of anthrones to activated alkenes are discussed. The reaction between anthrone or dithranol and α,β-unsaturated aldehydes is catalyzed by diphenylprolinol trimethylsilyl ether in toluene at −40 °C, giving the Michael adducts with good yields and enantioselectivities. Bifunctional amino-thioureas efficiently catalyze the additions of anthrones to both nitroalkenes and maleimides
Bifunctional Thiourea-Catalyzed Asymmetric Addition of Anthrones to Maleimides
作者:Alex Zea、Guillem Valero、Andrea-Nekane R. Alba、Albert Moyano、Ramon Rios
DOI:10.1002/adsc.201000031
日期:——
For the first time, the addition of anthrones to maleimides catalyzed by bifunctional thiourea catalysts is reported. The thiourea moiety is able to activate the maleimide and the tertiary amine deprotonates the anthrone, furnishing the final Diels–Alder or Michael adducts in excellent yields and enantioselectivities.