(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.
与末端炔烃相比,(甲硫基)炔烃通常是热促进的、由Co2(CO)8催化的烯炔和炔炔的Pauson-Khand反应的优越底物,能够提供更高产率和增强的非对映选择性。还透露了依赖于使用2,2,2-三氟乙醇作为共溶剂的产率改善,以及对(乙氧基)炔烃的内选择性的明显偏好。