Synthesis of Cyclopentenones with Reverse Pauson–Khand Regiocontrol via Ni-Catalyzed C–C Activation of Cyclopropanone
作者:Yujin Jang、Vincent N. G. Lindsay
DOI:10.1021/acs.orglett.0c03246
日期:2020.11.20
A formal [3 + 2] cycloaddition between cyclopropanone and alkynes via Ni-catalyzed C–C bond activation has been developed, where 1-sulfonylcyclopropanols are employed as key precursors of cyclopropanone in the presence of trimethylaluminum. The transformation provides access to 2,3-disubstituted cyclopentenones with complete regiocontrol, favoring reverse Pauson–Khand products, where the large substituent
Diastereoselective Hydrogenation of Tetrasubstituted Olefins using a Heterogeneous Pt‐Ni Alloy Catalyst
作者:William A. Swann、Anish Yadav、Nicholas B. Colvin、Nicole K. Freundl、Christina W. Li
DOI:10.1002/anie.202317710
日期:2024.5.6
A Pt−Ni alloy nanocatalyst is developed for the diastereoselective directed hydrogenation of tetrasubstituted olefins in a cyclopentene scaffold. For this substrate class, established homogeneous catalysts generate hydrogenolysis side products, and commercial heterogeneous catalysts are not stereoselective. Uniform alloying of the noble metal and base metal combined with high catalyst dispersion is