Asymmetric anti-Mannich reactions in continuous flow
作者:Rafael Martín-Rapún、Sonia Sayalero、Miquel A. Pericàs
DOI:10.1039/c3gc41444b
日期:——
A polystyrene-supported, pyrrolidine-based catalyst depicting very high activity and excellent stereoselectivity in the anti-Mannich reaction of aldehydes and ketones has been developed. The very robust, immobilized catalyst has been successfully used in the implementation of a continuous flow process with short residence times (down to 6 min) for the production of highly enantioenriched anti-type Mannich adducts at the preparative scale.
Mannich-type reactions of a glyoxylate imine with carbonyl compounds catalyzed by 3-trifluoromethanesulfonamidopyrrolidine proceed with high yields and anti-stereoselectivity. The catalyst is easily prepared and the transformation appears to be quite general accommodating aldehydes or ketones.
Highly Active Organocatalysts for Asymmetric anti-Mannich Reactions
作者:Rafael Martín-Rapún、Xinyuan Fan、Sonia Sayalero、Mahboubeh Bahramnejad、Félix Cuevas、Miquel A. Pericàs
DOI:10.1002/chem.201101513
日期:2011.8.1
of enantiopure 4‐oxy‐substituted 3‐aminopyrrolidines arising from the enantioselective ring‐opening of meso‐3‐pyrroline oxide have been developed as catalysts for the asymmetric, anti‐selective Mannichreaction (see scheme; PMP=p‐methoxyphenyl; PG=protecting group). Very high catalytic activity (down to 0.01 mol % loading) and stereoselectivity have been recorded.