Asymmetric Hydrogenation of α-Primary and Secondary Amino Ketones: Efficient Asymmetric Syntheses of (−)-Arbutamine and (−)-Denopamine
作者:Gao Shang、Duan Liu、Scott E. Allen、Qin Yang、Xumu Zhang
DOI:10.1002/chem.200700594
日期:2007.9.17
Two beta-receptor agonists (-)-denopamine and (-)-arbutamine were prepared in good yields and enantioselectivities by asymmetrichydrogenation of unprotected aminoketones for the first time by using Rh catalysts bearing electron-donating phosphine ligands. A series of alpha-primary and secondaryaminoketones were synthesized and hydrogenated to produce various 1,2-amino alcohols in good yields and
Tertiary amides, ureas, and amines undergo direct intermolecular addition to aldehydes under the Et3B/air conditions, thereby providing a unique and simple means for the radical sp3 C-H transformation of nitrogen-containing molecules.
Coupling Reaction between Aldehydes and Non-Activated Hydrocarbons via the Reductive Radical-Polar Crossover Pathway
Herein, we describe the generation of an organochromium-type carbanion species from a non-activated C-H bond and its nucleophilic addition to aldehydes. The catalytic carbanion generation occurred through formal deprotonation of a non-activated C-H bond under mild conditions and did not need the prefunctionalization or anion stabilizing group. Carbon radical intermediates generated by decatungstate