The Proline-Catalyzed Double Mannich Reaction of Acetaldehyde with<i>N</i>-Boc Imines
作者:Carley Chandler、Patrizia Galzerano、Anna Michrowska、Benjamin List
DOI:10.1002/anie.200806049
日期:2009.3.2
Double‐cross: Proline catalyzes the doubleMannichreaction of acetaldehyde with N‐Boc imines in excellent yields (up to 99 %; Boc=tert‐butoxycarbonyl) and close to perfect diastereo‐ and enantioselectivities. Depending on the choice of catalysts, both the chiral, pseudo‐C2‐symmetric diastereomer and the corresponding meso compound can be prepared. Cross doubleMannichreactions of acetaldehyde with
Facile Access to Chiral Ketones through Metal-Free Oxidative CC Bond Cleavage of Aldehydes by O2
作者:Bhoopendra Tiwari、Junmin Zhang、Yonggui Robin Chi
DOI:10.1002/anie.201107473
日期:2012.2.20
the boot: The title reaction provides facile access to functionalized chiralketones from chiral α,α′‐disubstituted aldehydes in the presence of molecular oxygen (see scheme). The CC bond‐cleavage approach offers an alternative or better method relative to the typical bond‐forming strategies used in synthesizing chiralketones.