Highly regio- and stereoselective hydrosilylation of β-fluoroalkylated α,β-unsaturated ketones
作者:Natsumi Ikeda、Tsutomu Konno
DOI:10.1016/j.jfluchem.2015.02.010
日期:2015.5
Treatment of β-fluoroalkylated α,β-unsaturated ketones with 10.2 equiv of triethylsilane in the presence of 3 mol% of Co2(CO)8 in dichloroethane at the reflux temperature for 4 h gave 1,4-hydrosilylated adducts in a highly regio- and stereoselective manner. Thus-obtained silyl enol ethers underwent a smooth Mukaiyama aldol reaction with benzaldehyde in the presence of 1.2 equiv of TiCl4 in CH2Cl2 at
Ferrocene Derived Bifunctional Phosphine-Catalyzed Asymmetric Oxa-[4+2] Cycloaddition of α-Substituted Allenones with Enones
作者:Huamin Wang、Weike Lu、Junliang Zhang
DOI:10.1002/chem.201703368
日期:2017.10.4
An efficient ferrocene‐derived bifunctional phosphine‐catalyzed enantioselective oxa‐[4+2] cycloaddition of α‐substituted allenones with a broad range of enones is investigated for the preparation of stereodefined dihydropyrans in good to excellent yields (up to 99 %) and excellent enantioselectivity (up to 99 % ee). Furthermore, a series of valuable chiral polyheterocyclic frameworks can be efficiently
The reaction of β-fluoroalkylated α,β-unsaturated ketones with various enamines gave 4-fluoroalkylated 3,4-dihydro-2H-pyrans as a major product in good yields by a one-pot operation, and these products display the high diastereoselection just after single recrystallization. This unexpected result is rationalized by the unique reactivity of β-fluoroalkylated α,β-unsaturated ketones. As the synthetic
Phosphine-Catalyzed Asymmetric Intermolecular Cross Rauhut-Currier Reaction of β-Perfluoroalkyl-Substituted Enones and Vinyl Ketones
作者:Mengna Tao、Wei Zhou、Junliang Zhang
DOI:10.1002/adsc.201700666
日期:2017.10.4
The highly enantioselective N‐acylaminophosphine‐catalyzed challenging asymmetric intermolecular cross Rauhut–Currierreaction of vinyl ketones with β‐perfluoroalkyl enones is described, which provides a facile access to chiralmultifunctional compounds bearing a perfluoroalkyl‐substituted stereocenter in good yields and ees.
Highly enantioselective [3+2] cycloadditions of terminal allenoates with β-trifluoromethyl α,β-enones
作者:Maizhan Li、Wei Zhou
DOI:10.1039/d0cc02876b
日期:——
Highly enantio- and diastereoselective phosphine-catalyzed [3+2] cycloadditions of terminal allenoates with β-perfluoroalkyl α,β-enones leading to a range of trifluoromethylated cyclopentenes with two contiguous chiral centers (up to 99% yield with 99% ee) have been developed. Moreover, these reactions could be performed at the gram scale by using only 1 mol% catalyst. The method developed here was