Visible‐Light Induced C‐3 Carbamoylation of Quinoxalinones Assisted by EDA Complex
摘要:
A visible‐light‐promoted strategy for the decarboxylative C‐3 carbamoylation of quinoxalinone scaffolds is developed. This approach initiates through the formation of an EDA complex between oxamic acid and quinoxalinone. Successive SET and decarboxylative carbamoylation construct the C‒C bond. This method utilizes aerial oxygen as the green oxidant and eradicates the process from the use of external photocatalysts and transition metals. Detailed synthetic and photophysical studies enlighten the reaction pathway.
Alkyl Carbazates for Electrochemical Deoxygenative Functionalization of Heteroarenes
作者:Yongyuan Gao、Zhengguang Wu、Lei Yu、Yi Wang、Yi Pan
DOI:10.1002/anie.202001571
日期:2020.6.26
work describes carbazate as a new type of electrochemically activated alkylatingagent derived from ubiquitous alcohols for direct functionalization of heteroarenes under mild electrolytic conditions. The simple undivided cell at low oxidative potentials with carbon/platinum electrode set‐ups offers excellent substrate tolerance, affording a variety of primary, secondary and tertiary alkyl‐decorated
Copper-Catalyzed Divergent C–H Functionalization Reaction of Quinoxalin-2(1<i>H</i>)-ones and Alkynes Controlled by N1-Substituents for the Synthesis of (<i>Z</i>)-Enaminones and Furo[2,3-<i>b</i>]quinoxalines
With control by N1-substituents, the switchable divergent C–H functionalization reaction of quinoxalin-2(1H)-ones is achieved for the synthesis of (Z)-enaminones and furo[2,3-b]quinoxalines using the combination of a copper catalyst and an oxidant. This new protocol features mild reaction conditions, readily available materials, and a broad substrate scope. Gram-scale and mechanistic studies were also
Photoinduced ligand to metal charge transfer enabling cerium mediated decarboxylative alkylation of quinoxalin-2(1<i>H</i>)-ones
作者:Swati Singh、Neha Dagar、Sudipta Raha Roy
DOI:10.1039/d2cc00840h
日期:——
direct use of carboxylic acids to access alkyl radicals. Spectroscopic investigations reveal the photoinduced LMCT and CO2 evolving events. We have utilized a broad range of alkyl carboxylic acids (1° to 3° acids), amino acids and pharmaceutically-important acids as a coupling partner to synthesise the desired alkylatedheterocyclic product in good to excellent yields.
在这里,我们报告了使用原料羧酸作为自由基前体通过光诱导 LMCT 对 quinoxalin-2(1 H )-ones进行铈介导的脱羧烷基化。这种操作简单的协议克服了直接使用羧酸获得烷基自由基的限制。光谱研究揭示了光诱导的 LMCT 和 CO 2演化事件。我们利用广泛的烷基羧酸(1° 至 3° 酸)、氨基酸和药学上重要的酸作为偶联伙伴,以良好至优异的产率合成所需的烷基化杂环产物。
Electro-oxidation induced O–S cross-coupling of quinoxalinones with sodium sulfinates for synthesizing 2-sulfonyloxylated quinoxalines
作者:Shi-Hui Shi、Jian Wei、Chun-Miao Liang、Huan Bai、Hai-Tao Zhu、Yantu Zhang、Feng Fu
DOI:10.1039/d2cc04524a
日期:——
C2 functionalized quinoxalinones is not reported via environmentally friendly approach. Herein, we disclosed C2–O sulfonylation of quinoxalinones via our developed electrochemical oxidative O–S coupling strategy for synthesizing 2-sulfonyloxylated quinoxalines. Applying this protocol, quinoxalin-ones and sodiumsulfinates as the starting materials, a wide range of 2-sulfonyloxyl quinoxaline derivatives