Highly Diastereo- and Enantioselective Silver-Catalyzed Double [3+2] Cyclization of α-Imino Esters with Isocyanoacetate
作者:Pan-Lin Shao、Jia-Yu Liao、Yee Ann Ho、Yu Zhao
DOI:10.1002/anie.201402788
日期:2014.5.19
Presented herein is a new complexity‐generating method in which both functionalities of α‐imino esters undergo stereoselective cyclization with isocyanoacetates to produce directly linked oxazole‐imidazolines, which can be transformed into highly functionalized α,β‐diamino esters and imidazolinium salts in high diastereo‐ and enantiopurity.
Silver-catalyzed cross-dehydrogenative coupling of benzoxazine-2-ones with resorcinol
作者:Yumi Kang、Soomin Jeon、Hayoung Kim、Jonghyeok Han、Garam Choi、Eun-Kyu Sun、Rameshwar Prasad Pandit、Tae-Hyun Kim
DOI:10.1016/j.tetlet.2022.154184
日期:2022.11
Silver-catalyzed cross-dehydrogenative coupling of benzoxazin-2-ones with resorcinol is reported. This method provides an easy and direct C3-arylation of benzoxazin-2-ones at ambient condition at the expenses of inexpensive ammonium persulfate as an oxidant. A radical pathway has been proposed for the transformation.
In this study, we have developed solvent‐controlled regioselective Mannich reaction of cyclicimines (benzoxazinones) with various ketones by using ʟ‐proline as catalyst to afford Mannich products in high yields with excellent enantio‐ and diastereoselectivity. The unsymmetrical ketones produced the linear isomer as the major product in chloroform solvent. On contrary, using the DMSO solvent favoured
Transition-Metal-Free Alkylation and Acylation of Benzoxazinones with 1,4-Dihydropyridines
作者:Youjung Byun、Junghyea Moon、Won An、Neeraj Kumar Mishra、Hyung Sik Kim、Prithwish Ghosh、In Su Kim
DOI:10.1021/acs.joc.1c01558
日期:2021.9.3
vital transformation for the development of pharmaceuticals, functional materials, and other chemical entities. Herein, the transition-metal-free alkylation and acylation of C(sp2)–H bonds in biologically relevant 2-benzoxazinones with 1,4-dihydropyridines as readily accessible radical surrogates is described. Excellent functional group compatibility and a broad substrate scope were attained. Gram-scale