Chang F,
Wang S,
Zhao Z,
Wang L,
Cheng T,
Liu G.
*
Shanghai Normal University, P. R. of China
Enantioselective Dual-Catalysis: A Sequential Michael Addition/Asymmetric Transfer
Hydrogenation of α-Nitrosulfone and Enones.
ACS Catal. 2020;
10: 10381-10389
DOI:
10.1021/acscatal.0c01559
Key words
dual catalysis - one-pot synthesis - organocatalysis - ruthenium catalysis - asymmetric
catalysis - Michael addition
Significance
A one-pot two-step asymmetric Michael addition–transfer hydrogenation co-catalyzed
by an immobilized organocatalyst [SA@HSMSN (Cat. A)] and a Ru complex catalyst {[Ru]@HSMSN/HP (Cat. B)} was developed. The reaction of enone 1 and nitro sulfone 2 in the presence of Cat. A, Cat. B, and HCO2Na gave the corresponding alcohols 4 in excellent chemical yields and with high diastereoselectivity (96–99% ee).
Comment
Squaramide and MesRuArDPEN were immobilized in hollow-shell-mesostructured silica
nanoparticles without or with a hydrophilic polymer coating to form Cat. A and Cat. B, respectively. Cat. A promoted the Michael addition at –35 °C, and Cat. B catalyzed the transfer hydrogenation at 35 °C, to realize temperature-dependent control
of the sequential dual-catalytic process.
