Direct arylation of cyclopentanones has been a long‐standing challenge because of competitive self‐aldol condensation and multiple arylations. Reported herein is a direct mono‐α‐C−H arylation of cyclopentanones with aryl bromides which is enabled by palladium/amine cooperative catalysis. This method is scalable and chemoselective with broad functional‐group tolerance. Application to controlled sequential
Versatile Access to Chiral Indolines by Catalytic Asymmetric Fischer Indolization
作者:Alberto Martínez、Matthew J. Webber、Steffen Müller、Benjamin List
DOI:10.1002/anie.201301618
日期:2013.9.2
for complexity: The chiral Brønsted acid (R)‐STRIP catalyzes the asymmetricFischerindolization of a range of monosubstituted cyclopentanones and cyclohexanones to give chiral fused indolines bearing a quaternary stereogenic center at the 3‐position. The method has been extended to include substrates bearing a tethered nucleophile, thus allowing for enantioselective indolization/ring‐closing cascades
A kineticresolution of racemic 2-substituted cyclopentanones via highly regio- and enantioselective Baeyer–Villiger oxidation has been successfully developed. The reaction could afford the normal 6-substituted δ-lactones in up to 98% ee and >19/1 regioselectivity. Meanwhile, the unreacted ketones were recovered in excellent ee values (up to 98%). It represents the best results of the kinetic resolution