2,2-dimethyl-5-(5-r-furfurylidene)-1,3-dioxane4,6 diones 7. Synthesis, structure, and properties of 2,2dimethyl-5-(3-furfuryldiene and 3-thienylidene)-1,3dioxane-4,6-diones
作者:G. D. Krapivin、N. I. Val'ter、V. E. Zavodnik、D. Vegkh、L. Fishera、V. G. Kul'nevich
DOI:10.1007/bf01170736
日期:1995.7
Gold(I)-Catalyzed<i>endo</i>-Selective Intramolecular α-Alkenylation of β-Yne-Furans: Synthesis of Seven-Membered-Ring-Fused Furans and DFT Calculations
Alkenylation of furans: An efficient gold‐catalyzed endo‐selective intramolecular α‐alkenylation of β‐alkyne‐substituted furans has been developed to synthesize challenging seven‐membered‐ring‐fused furans in good to excellent yields. Preliminary DFTcalculations have been carried out to understand the experimentally observed regioselectivity. DME=1,2‐dimethoxyethane, Ts=p‐toluenesulfonyl.
Asymmetric Synthesis of α-Trifluoromethylthio-β-Amino Acids under Phase Transfer Catalysis
作者:Vito Capaccio、Marina Sicignano、Ricardo I. Rodríguez、Giorgio Della Sala、José Alemán
DOI:10.1021/acs.orglett.9b04195
日期:2020.1.3
The first asymmetric α-trifluoromethylthiolation of 2-substituted isoxazolidin-5-ones was developed using Maruoka type N-spiro ammonium catalysts under phase-transfer conditions. The resulting products, containing a trifluoromethylthiolated quaternary chiral carbon, were obtained in moderate to good yields and up to 98:2 enantiomeric ratio. Moreover, the easy N-O bond cleavage provided access to undescribed