Diastereoselective Reduction of Alkenylboronic Esters as a New Method for Controlling the Stereochemistry of up to Three Adjacent Centers in Cyclic and Acyclic Molecules
摘要:
[GRAPHIC]cis-Boronates are readily available via a diastereoselective Pd-catalyzed reduction of tetrasubstituted alkenylboronic esters using H-2. Applying the reaction conditions presented to unsaturated open-chain boronic esters allows the stereochemistry of up to three adjacent centers to be controlled.
Palladium-catalyzed asymmetric hydrogenation of 2-aryl cyclic ketones for the synthesis of <i>trans</i> cycloalkanols through dynamic kinetic resolution under acidic conditions
The first efficient palladium-catalyzed asymmetric hydrogenation of 2-aryl cyclic ketones has been described through dynamickineticresolution under acidic conditions, providing a facile access to chiral trans cycloalkanol derivatives with excellent enantioselectivities.
Acid instead of base: Kineticresolution of secondary alcohols is realized using chiral Brønsted acid catalyzed acylation instead of the conventional basic conditions. A broad range of functional groups are tolerated, such as aldehydes, carboxylic acids, and enoates. The selectivity factor (s) reaches up to 215 at ambient temperature.
Asymmetric Hydrogenation of 2-Arylated Cycloalkanones through Dynamic Kinetic Resolution
作者:Ryoji Noyori、Takeshi Ohkuma、Jing Li
DOI:10.1055/s-2004-829093
日期:——
Asymmetric hydrogenation of 2-arylcycloalkanones with trans-RuCl2(binap)(1,2-diamine) and t-C4H9OK in 2-propanol selectively gives the corresponding cis-2-arylcycloalkanols in excellent enantiomeric purity and high yield. Two synthetic intermediates of biologically active compounds have been prepared by this method.
Diastereoselective Reduction of Alkenylboronic Esters as a New Method for Controlling the Stereochemistry of up to Three Adjacent Centers in Cyclic and Acyclic Molecules
作者:Eike Hupe、Ilan Marek、Paul Knochel
DOI:10.1021/ol0262486
日期:2002.8.1
[GRAPHIC]cis-Boronates are readily available via a diastereoselective Pd-catalyzed reduction of tetrasubstituted alkenylboronic esters using H-2. Applying the reaction conditions presented to unsaturated open-chain boronic esters allows the stereochemistry of up to three adjacent centers to be controlled.