Organocatalytic Redox Isomerization of Electron-Deficient Allylic Alcohols: Synthesis of 1,4-Ketoaldehydes
作者:Keshab Mondal、Buddhadeb Mondal、Subhas Chandra Pan
DOI:10.1021/acs.joc.6b00243
日期:2016.6.3
An organocatalytic redox isomerization strategy has been developed for the synthesis of 1,4-ketoaldehydes. DABCO was found to be the best catalyst for the isomerization of γ-hydroxy enones. With 20 mol % of DABCO as catalyst and DMSO as the solvent high yields have been achieved for different 1,4-ketoaldehydes.
Lewis Acid Catalyzed [3+3] Annulation of Donor-Acceptor Cyclopropanes with γ-Hydroxyenones: Access to Highly Functionalized Tetrahydropyrans
作者:Keshab Mondal、Subhas Chandra Pan
DOI:10.1002/ejoc.201601305
日期:2017.1.18
Donor–acceptorcyclopropanes were engaged in a [3+3]-annulation reaction with γ-hydroxyenones. Sc(OTf)3 was found to be the best catalyst, and 2,4,4,5-tetrasubstituted tetrahydropyran products were obtained in good yields under mild reaction conditions. The generality of the reaction permitted the synthesis of tetrasubstituted tetrahydropyrans bearing aryl, alkyl, and heteroaromatic groups. A catalytic