α-MsO/TsO/Cl Ketones as Oxidized Alkyne Equivalents: Redox-Neutral Rhodium(III)-Catalyzed CH Activation for the Synthesis of N-Heterocycles
作者:Da-Gang Yu、Francisco de Azambuja、Frank Glorius
DOI:10.1002/anie.201310272
日期:2014.3.3
α‐Halo and pseudohalo ketones are used for the first time as C(sp3)‐based electrophiles in transition‐metal‐catalyzed CHactivation and as oxidizedalkyneequivalents in RhIII‐catalyzed redox‐neutral annulations to generate diverse N‐heterocycles. This transformation is efficient and scalable. Due to the mild reaction conditions, a variety of functional groups could be tolerated.
Access to divergent benzo-heterocycles via a catalyst-dependent strategy in the controllable cyclization of o-alkynyl-N-methoxyl-benzamides
作者:Dong Ding、Tao Mou、Jiahui Xue、Xuefeng Jiang
DOI:10.1039/c7cc01861d
日期:——
regio-selectively controllable approach for construction of diverse benzo-heterocycles is established. A new strategy for using the ligand effect in gold catalysis to control the regioselectivity in the cyclization of o-alkynyl-N-methoxyl-benzamide is successfully achieved. Meanwhile, the chemoselectivity between nitrogen and oxygen nucleophiles is precisely switched by gold and platinumcatalysts.
Rhodium(<scp>iii</scp>)-catalyzed chemodivergent annulations between <i>N</i>-methoxybenzamides and sulfoxonium ylides <i>via</i> C–H activation
作者:Youwei Xu、Guangfan Zheng、Xifa Yang、Xingwei Li
DOI:10.1039/c7cc07753j
日期:——
Chemodivergent and redox-neutral annulations between N-methoxybenzamides and sulfoxonium ylides have been realized via Rh(III)-catalyzed C–H activation. The sulfoxonium ylide acts as a carbene precursor, and coupling occurs under acid-controlled conditions, where Zn(OTf)2 and PivOH promote chemodivergent cyclizations.
Tunable Synthesis of 3-Hydroxylisoquinolin-1,4-dione and Isoquinolin-1-one Enabled by Copper-Catalyzed Radical 6-<i>endo</i> Aza-cyclization of 2-Alkynylbenzamide
In this work, switchable synthesis of isoquinolin-1-one and 3-hydroxylisoquinolin-1,4-dione from 2-alkynylbenzamide is reported. The transformation works well with good yields and a broad reaction scope. The synthetic switch for providing isoquinolin-1-one and 3-hydroxylisoquinolin-1,4-dione is enabled by the use of a N2 or O2 atmosphere. Mechanism studies show that the reaction proceeds in a regioselective