[EN] PROCESS FOR THE PREPARATION OF MEMANTINE AND ITS SALTS AND INTERMEDIATE FOR USE THEREIN [FR] PROCÉDÉ DE PRÉPARATION DE LA MÉMANTINE ET DE SES SELS ET INTERMÉDIAIRE DESTINÉ À ÊTRE UTILISÉ DANS CE PROCÉDÉ
A highly tunable radical-mediated reaction system for the functionalization of tertiary aliphatic C–Hbonds was developed. Reactions of various substrates with the Zhdankin azidoiodane reagent 1, Ru(bpy)3Cl2, and visible light irradiation at room temperature gave C–H azidated or halogenated products in an easily controllable fashion. These reactions are efficient, selective, and compatible with complex
A unified photoredox-catalysis strategy for C(sp<sup>3</sup>)–H hydroxylation and amidation using hypervalent iodine
作者:Guo-Xing Li、Cristian A. Morales-Rivera、Fang Gao、Yaxin Wang、Gang He、Peng Liu、Gong Chen
DOI:10.1039/c7sc02773g
日期:——
unified photoredox-catalysis strategy for both hydroxylation and amidation of tertiary and benzylic C-H bonds. Use of hydroxyl perfluorobenziodoxole (PFBl-OH) oxidant is critical for efficient tertiary C-H functionalization, likely due to the enhanced electrophilicity of the benziodoxole radical. Benzylic methylene C-H bonds can be hydroxylated or amidated using unmodified hydroxyl benziodoxole oxidant Bl-OH
Site-Selective Aliphatic C–H Bromination Using <i>N</i>-Bromoamides and Visible Light
作者:Valerie A. Schmidt、Ryan K. Quinn、Andrew T. Brusoe、Erik J. Alexanian
DOI:10.1021/ja508469u
日期:2014.10.15
Transformations that selectively functionalize aliphatic C-H bonds hold significant promise to streamline complex molecule synthesis. Despite the potential for site-selective C-H functionalization, few intermolecular processes of preparative value exist. Herein, we report an approach to unactivated, aliphatic C-H bromination using readily available N-bromoamide reagents and visible light. These halogenations
of tertiary and secondary benzylic C(sp3)-H, aliphatic C(sp3)-H, and drug-molecules-based C(sp3)-H bonds containing in substrates are well tolerated under our protocol. The simultaneous gram-scale synthesis and the ease of transformation of azide to amine collec-tively advocate for the potential application in the preparative syn-thesis. Good reactivity of tertiary benzylic C(sp3)-H bond and se-lectivity
C–H Alkylation via Multisite-Proton-Coupled Electron Transfer of an Aliphatic C–H Bond
作者:Carla M. Morton、Qilei Zhu、Hunter Ripberger、Ludovic Troian-Gautier、Zi S. D. Toa、Robert R. Knowles、Erik J. Alexanian
DOI:10.1021/jacs.9b06834
日期:2019.8.21
The direct, site-selective alkylation of unactivated C(sp3)-H bonds in organic substrates is a long-standing goal in synthetic chemistry. General approaches to the activation of strong C-H bonds include radical-mediated processes involving highly reactive intermediates, such as heteroatom-centered radicals. Herein, we describe a catalytic, intermolecular C-H alkylation that circumvents such reactive