(Alkylthio)alkynes as Addends in the Co(0) Catalyzed Intramolecular Pauson-Khand Reaction. Substituent Driven Enhancements of Annulation Efficiency and Stereoselectivity
(Alkylthio)alkynes as Addends in the Co(0) Catalyzed Intramolecular Pauson-Khand Reaction. Substituent Driven Enhancements of Annulation Efficiency and Stereoselectivity
(Alkylthio)alkynes as Addends in the Co(0) Catalyzed Intramolecular Pauson-Khand Reaction. Substituent Driven Enhancements of Annulation Efficiency and Stereoselectivity
作者:Brian L. Pagenkopf、David B. Belanger、Donogh J. R. O'Mahony、Tom Livinghouse
DOI:10.1055/s-2000-6301
日期:——
Compared to terminal alkynes, (methylthio)alkynes are generally superior substrates for the thermally promoted, Co2(CO)8 catalyzed Pauson-Khand reaction of enynes and allenynes, providing enones in higher yields and with enhanced diastereoselectivity. Improvements in yield dependent upon the use of 2,2,2-trifluoroethanol as co-solvent and an apparent preference for endo selectivity with (ethoxy)alkynes are also disclosed.