Conjugated imines and iminium salts as versatile acceptors of nucleophiles
作者:Makoto Shimizu、Iwao Hachiya、Isao Mizota
DOI:10.1039/b814930e
日期:——
development of synthetic methodologies where nucleophilicaddition reactions to imino carbons are utilized in crucial steps. This article summarizes double nucleophilicaddition reactions with alpha,beta-unsaturated aldimines, addition reactions using alkynyl imines, "umpoled" reactions of alpha-imino esters, and the use of iminium salts as reactive electrophiles.
A two-pot synthesis of 5-aza-indoles has been developed from aqueous succinaldehyde and N-aryl propargylic-imines. This overall protocol involves: (i) the metal-free [3 + 2] annulation of aqueous succinaldehyde and N-aryl propargylic-imines to access 2-alkynyl-pyrrole-3-aldehydes and (ii) Ag-catalyzed 6-endo-dig-cyclization to obtain substituted 5-aza-indoles in the second pot. The 5-aza-indoles showed
已经从水性琥珀醛和N-芳基炔丙基亚胺开发了 5-氮杂-吲哚的两锅法合成。该总体方案包括:(i) 水性琥珀醛和N-芳基炔丙基-亚胺的无金属 [3 + 2] 环化以获取 2-炔基-吡咯-3-醛和 (ii) Ag 催化的 6- endo-在第二个锅中进行dig环化以获得取代的 5-aza-indoles。5-氮杂吲哚表现出引人入胜的光物理活性,并且已经证明了这种罐经济克级合成的实用性。
Multicomponent Assembly of Complex Oxindoles by Enantioselective Cooperative Catalysis
作者:Ru‐Yu Hua、Si‐Fan Yu、Xiao‐Ting Jie、Huang Qiu、Wen‐Hao Hu
DOI:10.1002/anie.202213407
日期:2022.12.19
Ternary catalysis enabled the three-component reaction of N-aryl diazoamides, aldehydes, and enamines/indoles, providing access to polyfunctionalized oxindoles in good yields with excellent diastereoselectivities and enantioselectivities (>90 examples, up to 94 % yield, 99 % ee, and >20 : 1 dr). The reaction involves the assembly of two highly reactive intermediates generated in situ by orthogonal
Synthesis of multi -substituted 2-aminopyridinium.salts is developed using 2-iminopyridines as a starting material. The reactions of multi -substituted 2-iminopyridines prepared by the conjugate addition of ethyl 2-cyanopropanoate to alkynyl imines with several acids proceeded smoothly to give multi-substituted 2-aminopyridinium salts in high yields.
Piterskaya; Khramchikhin; Stadnichuk, Russian Journal of General Chemistry, 1996, vol. 66, # 7, p. 1150 - 1157