A highly efficient enantio- and diastereoselective synthesis of chiral cis-β-N-alkyl/arylamino cyclic alcohols has been realized by asymmetric hydrogenation of racemic α-amino cyclic ketones via DKR catalyzed by [RuCl2((S)-Xyl-SDP)((R,R)-DPEN)]. The enantioselectivities of the reaction were up to 99.9% ee with 99:1 cis-selectivities. A practical catalytic asymmetric synthesis of all four isomers of
Rh‐Catalyzed Chemodivergent [3+3] Annulations of Diazoenals and α‐Aminoketones: Direct Synthesis of Functionalized 1,2‐Dihydropyridines and Fused 1,4‐Oxazines
作者:Pratap Kumar Mandal、Sreenivas Katukojvala
DOI:10.1002/chem.202303862
日期:2024.4.2
Chemodivergent [3+3] annulations: The reactivity of Rh-enalcarbenoid has been switched from carbenoid to vinylogous NH-insertion by altering acyclic to cyclic α-amino ketones to deliver functionalized 1,2-dihydropyridines (1,2-DHPs) and fused 1,4-oxazines respectively. The structural diversification of 1,2-DHP and fused 1,4-oxazines gave valuable piperidines, pyrido[1,2-a]indole, 2-pyridone, hexahydroquinolin-2(1H)-ones