Chiral Brønsted Acid-Catalyzed Direct Asymmetric Mannich Reaction
作者:Qi-Xiang Guo、Hua Liu、Chang Guo、Shi-Wei Luo、Yi Gu、Liu-Zhu Gong
DOI:10.1021/ja068236b
日期:2007.4.1
A chiral Bronsted acid-catalyzed direct asymmetric Mannich reaction has been described. Various phosphoric acids, prepared from BINOL and H-8-BINOL derivatives, have been evaluated for catalyzing the direct Mannich reaction. In the presence of a truly catalytic amount of the phosphoric acid, anti-selective Mannich reactions of cyclic ketones with a wide scope of aldimines were obtained in high yields with excellent enantioselectivities (up to 98% ee) and high diastereomeric ratios (up to 98/2 dr). A one-pot Mannich reaction using aromatic ketones as donors proceeded smoothly to give beta-amino carbonyls with fairly good enantioselectivities.
Antiselective Three-Component Mannich Reactions in Thiopyran-4-one System
作者:M. Saeed Abaee、Mohammad M. Mojtahedi、Ali Akbari、Ehsan Mehraki、A. Wahid Mesbah、Klaus Harms
DOI:10.1002/jhet.976
日期:2012.11
The one‐pot, three‐component Mannichreactions of thiopyran‐4‐one 1 with different aromatic aldehydes and aniline derivatives in the presence of catalytic quantities of ZrOCl2.8H2O (15 mol %) led to rapid and high yield formation of various 3‐methylamino substituted derivatives of 1 at room temperature. Spectroscopic and X‐ray analyses of the products suggested the formation of the anti stereoisomers