446065-11-8Relevant articles and documents
Manganese(III)-Promoted Double Carbonylation of Anilines Toward α-Ketoamides Synthesis
Chen, Bo,Kuai, Chang-Sheng,Xu, Jian-Xing,Wu, Xiao-Feng
supporting information, p. 487 - 492 (2021/12/06)
Employing anilines as nucleophiles in double carbonylation is a longstanding challenge. In this communication, a Mn(III)-promoted double carbonylation of alkylborates or Hantzsch esters with anilines toward the synthesis of α-ketoamides has been developed. By using easily available potassium alkyltrifluoroborates or Hantzsch esters as the starting material, and cheap and non-toxic Mn(OAc)3 ? 2H2O as the promotor, a broad range of alkyl α-ketoamide derivatives were synthesized in moderate to good yields with excellent selectivity. (Figure presented.).
Intermolecular Radical Addition to Ketoacids Enabled by Boron Activation
Xie, Shasha,Li, Defang,Huang, Hanchu,Zhang, Fuyuan,Chen, Yiyun
supporting information, p. 16237 - 16242 (2019/10/14)
The intermolecular radical addition to the carbonyl group is difficult due to the facile fragmentation of the resulting alkoxyl radical. To date, the intermolecular radical addition to ketones, a valuable approach to construct quaternary carbon centers, remains a formidable synthetic challenge. Here, we report the first visible-light-induced intermolecular alkyl boronic acid addition to α-ketoacids enabled by the Lewis acid activation. The in situ boron complex formation is confirmed by various spectroscopic measurements and mechanistic probing experiments, which facilitates various alkyl boronic acid addition to the carbonyl group and prevents the cleavage of the newly formed C-C bond. Diversely substituted lactates can be synthesized from readily available alkyl boronic acids and ketoacids at room temperature merely under visible light irradiation, without any additional reagent. This boron activation approach can be extended to alkyl dihydropyridines as radical precursors with external boron reagents for primary, secondary, and tertiary alkyl radical additions. The pharmaceutically useful anticholinergic precursors are easily scaled up in multigrams under metal-free conditions in flow reactors.
Investigations of alkynylbenziodoxole derivatives for radical alkynylations in photoredox catalysis
Pan, Yue,Jia, Kunfang,Chen, Yali,Chen, Yiyun
supporting information, p. 1215 - 1221 (2018/06/13)
The alkynylbenziodoxole derivatives are recently developed alkynylation reagents in organic synthesis, which demonstrate excellent radical alkynylation reactivity in photoredox catalysis reactions. Herein we report the synthesis of alkynylbenziodoxole derivatives with difluoro, monofluoro, monomethoxy, and dimethoxy substitution on the benziodoxole moiety, and investigated their radical alkynylation reactivity for the first time. A series of mechanistic experiments were conducted to study the radical acceptor and oxidative quencher reactivity of alkynylbenziodoxoles, in which unsubstituted alkynylbenziodoxoles played balancing roles in both processes, while electron-rich benziodoxole derivatives demonstrate synthetic advantages in some cases.