报道了在氧化条件下使用(二乙酰氧基碘)苯和K 2 S 2 O 8的组合,从N-吡啶基吲哚空前合成稠合的喹唑啉酮的报道。该反应是无金属的,具有广泛的底物范围,操作简单且反应时间短,并且以中等至高产率提供了11 H-吡啶并[2,1 - b ]喹唑啉-11酮衍生物。据信它是通过原位生成的2-羟基-1-(吡啶-2-基)吲哚-3-酮作为关键反应中间体进行的,该中间体经历CC键裂解产生亲电C-3位点在N-吡啶基吲哚中。吡啶氮随后的亲核攻击导致其环化。
Condensation of anthranilic acids with pyridines to furnish pyridoquinazolones via pyridine dearomatization
作者:Yajun Yang、Cuiju Zhu、Min Zhang、Shijun Huang、Jingjing Lin、Xiandao Pan、Weiping Su
DOI:10.1039/c6cc07365d
日期:——
The unprecedented carbodiimide-mediated condensation between pyridines and anthranilicacids via pyridines dearomatization at room temperature has been developed to provide a straightforward approach to pyridoquinazolones. The value of this approach...
Palladium/Silver Synergistic Catalysis in Direct Aerobic Carbonylation of C(sp<sup>2</sup>)<i>−</i>H Bonds Using DMF as a Carbon Source: Synthesis of Pyrido-Fused Quinazolinones and Phenanthridinones
作者:D. Nageswar Rao、Sk. Rasheed、Parthasarathi Das
DOI:10.1021/acs.orglett.6b01292
日期:2016.7.1
An unprecedented Pd/Ag synergistic catalysis in the direct carbonylation of C(sp2)–H bonds utilizing DMF as the carbon source under oxygen is described and demonstrated in the synthesis of pyrido-fused quinazolinone and phenanthridinone scaffolds. Control experiments indicated that the “C” of the carbonyl group is derived from the methyl group of DMF and “O” originates from oxygen as in the case of
Base-Controlled Selectivity in the Synthesis of Linear and Angular Fused Quinazolinones by a Palladium-Catalyzed Carbonylation/Nucleophilic Aromatic Substitution Sequence
A new approach for the facile synthesis of fused quinazolinone scaffolds through a palladium‐catalyzed carbonylative coupling followed by an intramolecular nucleophilic aromatic substitution is described. The base serves as the key modulator: Whereas DBU gives rise to the linear isomers, Et3N promotes the preferential formation of angular products. Interestingly, a light‐induced 4+4 reaction of the
A transition-metal-free C═C double bondcleavage reaction employing molecular iodine is described. In the presence of K2CO3 as the base, I2-mediated C═Cbondcleavage followed by intramolecular annulation of N-(2-vinylaryl)pyridin-2-amine substrates produces pyrido[2,1-b]quinazolinones and related heterocyclic compounds. This reaction can be completed on a gram scale and has been successfully applied
描述了使用分子碘的不含过渡金属的 C=C 双键断裂反应。在作为碱基的 K 2 CO 3存在下,I 2介导的 C=C 键断裂,随后N -(2-乙烯基芳基)吡啶-2-胺底物的分子内环化产生吡啶并[2,1- b ]喹唑啉酮和相关杂环化合物。该反应可以在克级上完成,并已成功应用于合成具有重要生物学特性的化合物,包括外排泵抑制和抗过敏活性。