Ion-pairing catalysis in the enantioselective addition of hydrazones to <i>N</i>-acyldihydropyrrole derivatives
作者:Nagore Zabaleta、Uxue Uria、Efraim Reyes、Luisa Carrillo、Jose L. Vicario
DOI:10.1039/c8cc05311a
日期:——
demonstrated that dihydropyrrole-based enamide derivatives can act as efficient precursors of chiral quaternary N-acyliminium salts under Brønsted acid catalysis that undergo reactions with hydrazones, the latter participating as masked nucleophilic carbonyl group equivalents. The optimized methodology provides a variety of enantiopure α-substituted proline derivatives in excellent yields, being even compatible
A biogenetically inspired heterodimerization approach to the synthesis of the core structure of the alkaloid fissoldhimine
作者:Heather Twin、Wendy W.-H. Wen、David A. Powell、Alan J. Lough、Robert A. Batey
DOI:10.1016/j.tetlet.2007.01.019
日期:2007.3
biogenetically inspired heterodimerization reaction of N-substituted 2-pyrroline equivalents leads to the tricyclic core of the alkaloid fissoldhimine. Thus, pyrrolidin-2-ol derivatives, in which the nitrogen atom is substituted either with urea or thiourea functionality, serve as equivalents of the corresponding N-substituted 2-pyrrolines. Reaction of these compounds under Lewis acidic (e.g., lanthanide