Abstractmagnified imageA highly enantioselective aza‐Henry reaction of imines with nitromethane was achieved with a reactive guanidine‐thiourea bifunctional organocatalyst affording β‐nitroamines with high enantioselectivity (up to 96% ee). The diastereo‐ and enantioselective version of this reaction with nitroalkanes also proceeded selectively (up to 99:1 dr with 99% ee).
Enantioselective Aza-Henry Reaction with an <i>N</i>-Sulfinyl Urea Organocatalyst
作者:MaryAnn T. Robak、Monica Trincado、Jonathan A. Ellman
DOI:10.1021/ja075653v
日期:2007.12.1
simultaneously acidify the urea and provide asymmetric induction in hydrogen-bond-catalyzed reactions. The utility of this new catalyst structure is demonstrated by the high selectivity provided in the aza-Henryreaction not only for aromatic N-Boc imine substrates but also for aliphatic imines for which enantioselective H-bonding catalysis has not previously been demonstrated.
A catalyticasymmetric nitro-Mannich (aza-Henry) reaction with rareearth metal/alkali metal heterobimetallic catalysts is described. A Yb/K heterobimetallic catalyst assembled by an amide-based ligand promoted the asymmetric nitro-Mannich reaction to afford enantioenriched anti-b-nitroamines in up to 86% ee. Facile reduction of the nitro functionality allowed for efficient access to optically active
描述了与稀土金属/碱金属异双金属催化剂的催化不对称硝基-曼尼希 (氮杂-亨利) 反应。由基于酰胺的配体组装的 Yb/K 杂双金属催化剂促进了不对称硝基-曼尼希反应,以提供高达 86% ee 的对映体富集的抗 b-硝基胺。硝基官能团的轻松还原允许有效获取光学活性 1,2-二胺。
Asymmetric aza-Henry reaction of BOC-protected imines with zinc-FAM catalyst
作者:Nurzhan Beksultanova、Özdemir Doğan
DOI:10.1080/00397911.2024.2303054
日期:2024.3.3
Derivatives of ferrocenyl-substituted aziridinyl methanol (FAM) ligands were used with zinc metal for asymmetric aza-Henry (nitro-aldol) reaction of N-Boc protected imines with nitroalkanes. At opt...
syn-Selective catalytic asymmetric nitro-Mannich reactions using a heterobimetallic Cu/Sm/Schiff base complex are described. The present method is complementary to the previously reported methods, and products were obtained in high syn-selectivity (> 20:1), yield (99-62%), and enantioselectivity (98-83% ee). Both Cu and Sm metals, aligned suitably in a dinucleating Schiff base ligand, were essential to realize high synselectivity.