The rhodium(III)-catalyzeddirectC–H addition and annulation of benzimidates and aldimines with β-(trifluoromethyl)-α,β-unsaturated ketones is described. This protocol provides the facile and efficient formation of various trifluoromethyl-containing indenamines or aminoindanes in moderate to high yields.
Chiral Hydroxytetraphenylene-Catalyzed Asymmetric Conjugate Addition of Boronic Acids to Enones
作者:Guo-Li Chai、A-Qiang Sun、Dong Zhai、Juan Wang、Wei-Qiao Deng、Henry N. C. Wong、Junbiao Chang
DOI:10.1021/acs.orglett.9b01637
日期:2019.7.5
(S)-2,15-Br2-DHTP-catalyzed asymmetric conjugate addition of boronic acids to β-trifluoromethyl α,β-unsaturated ketones and enones was studied. The reaction afforded the corresponding Michael addition products in moderate to high yields with excellent enantioselectivities (up to 99:1 er). This catalytic system features mild reaction conditions, high efficiency, and tolerance to heteroarylboronic acids
Rh(III)-Catalyzed Annulation of 2-Biphenylboronic Acid with Diverse Activated Alkenes
作者:Bingxian Liu、Lingyun Yang、Zhenzhen Dong、Junbiao Chang、Xingwei Li
DOI:10.1021/acs.orglett.1c02597
日期:2021.9.17
the reductive elimination process prior to protonolysis, affording the [4 + 2] annulated products instead of the simple 1,4-addition product. Seven-membered rings were obtained when disubstituted cyclopropenones were employed. Bridged cycles were isolated from the coupling of 2-biphenylboronic acid with benzoquinones as a result of 2-fold Michaeladditions. The substrate scopes were found to be broad
Catalytic Asymmetric Synthesis of Vicinally Bis(trifluoromethyl)-Substituted Molecules via Normal [3 + 2] Cycloaddition of <i>N</i>-2,2,2-Trifluoroethyl Benzothiophene Ketimines and β-Trifluoromethyl Enones
An organocatalytic asymmetric [3 + 2] cycloaddition of β-trifluoromethyl enones with 3-(N-2,2,2-trifluoroethyl) benzothiophene ketimines and 2-(N-2,2,2-trifluoroethyl) benzothiophene ketimines was described for the first time. A wide spectrum of vicinally bis(trifluoromethyl)-substituted spiro pyrrolidine-benzothiophenones were obtained with excellent stereocontrol (all cases >20:1 dr and up to 99%