Here we report a novel Rh-catalyzed C−H/C−H alkenylation of N-arylmethanimines with vinylene carbonate acting as a vinylene unit. Forty examples of C3,C4-nonsubstituted quinolines were achieved from commercially available starting materials. This identified process features an exceedingly simple system, a lower loading of catalyst, and the capacity for postfunctionalization with bioactive molecules.

Transition metal-catalyzed inert C-H annulation reaction, an efficient strategy in the field of organic chemistry, is capable of constructing a series of carbon-or heterocycle molecules. Very recently, organic chemists have commenced to employ vinylene carbonate as a carbon synthon for the efficient construction of non-substituted heterocyclic compounds, which benefits with the enriched product structure, quite simple and concise reaction system, and the sole carbonic acid as by-product. A new type of C-H [4＋2] cyclization reaction of quinazolinone with ethylene carbonate catalyzed by ruthenium is proposed, and 2,3-fused quinazolinone derivatives are obtained with good yields. Keywords ruthenium catalysis; C-H cyclization reaction; vinylene carbonate; fused quinazolone 喹唑啉酮作为一类极其重要的杂环化合物, 广泛存 在于众多活性天然产物与药物分子中 [1] . 因其在抗肿 瘤、抗惊厥、抗炎、抗疟、抗结核及抗高血压等 [2] 方面 的药学应用和生物活性受到化学与生物学家的广泛关 注. 其中, 2,3-稠合喹唑啉酮更是许多药物和天然产物 分子, 如吴茱萸次碱(rutecarpine)的核心子结构, 表现出 良好的抗炎、抗肿瘤和抗肥胖等药理活性 [3] . 此外, 2,3-稠合喹唑啉酮骨架在分子荧光探针和有机催化领域同 样具有潜在价值 [4] (Scheme 1, a). 因此, 开发简洁、高效 合成 2,3-稠合喹唑啉酮衍生物的方法十分重要.2,3-稠合喹唑啉酮骨架 的构建. 随后, Szostak 小组 [9] 发现硫叶立德在铑催化下 也可以作为 C2 合成子直接参与 C-H 环化反应, 得到 C(6)取代的 2,3-稠合喹唑啉酮衍生物. 尽管上述 C2 合成 有机化学 研究论文 1538 http://sioc-journal.cn/

Herein, we disclose a novel reorganization/cycloaddition between two imine units catalyzed by In(OTf)3 Lewis acid, which is sharply distinguished from the well-recognized [4+2] cycloaddition version with Povarov reaction. By means...

Reorganization of unsaturated chemical bonds is one of the most promising strategies to generate architecturally diversified and innovative molecular library. Herein, we disclose a novel reorganization/cycloaddition between two imine units catalyzed by In(OTf)3 Lewis acid, which is sharply distinguished from the well-recognized [4+2] cycloaddition version with Povarov reaction. By means of this unprecedented imine chemistry, a collection of synthetically useful dihydroacridines have been synthesized with high functional group compatibility under concise reaction conditions. Preliminary mechanistic studies unravel that α，β-unsaturated imine likely serves as a pivotal intermediate. Notably, handing products give rise to a series of structurally novel and fine-tuneable acridinium photocatalysts, which offers a heuristic paradigm for synthesizing these ones and is also highlighted by facilitating several encouraging dihydrogen coupling reactions efficiently.