simple and efficientsynthesis of 11H-pyrido[2,1-b]quinazolin-11-ones by Cu(OAc)2·H2O-catalyzed reaction of easily available substituted isatins and 2-bromopyridine derivatives has been developed. The reaction involves C–N/C–C bond cleavage and two C–N bond formations in a one-pot operation. This methodology is complementary to previously reported synthetic procedures, and two plausible reaction mechanisms
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
Copper-catalyzed domino sequences: a new route to pyrido-fused quinazolinones from 2′-haloacetophenones and 2-aminopyridines
作者:Phuc H. Pham、Son H. Doan、Ngan T. H. Vuong、Vu H. H. Nguyen、Phuong T. M. Ha、Nam T. S. Phan
DOI:10.1039/c8ra03744b
日期:——
A new pathway to access pyrido-fused quinazolinones via a Cu(OAc)2-catalyzed domino sequential transformation between 2′-haloacetophenones and 2-aminopyridines was demonstrated. The solvent and base exhibited a remarkable effect on the transformation, in which the combination of DMSO and NaOAc emerged as the best system. Cu(OAc)2·H2O was more active towards the reaction than numerous other catalysts
证明了通过2'-卤代苯乙酮和 2-氨基吡啶之间的 Cu(OAc) 2催化多米诺连续转化获得吡啶并稠合喹唑啉酮的新途径。溶剂和碱对转化效果显着,其中DMSO和NaOAc的组合是最佳体系。 Cu(OAc) 2 ·H 2 O 比许多其他催化剂对反应更具活性。这种方法是新的,将补充以前合成吡啶并稠合喹唑啉酮的方案。
Synthesis of 9‐Methyl‐11H‐pyrido[2,1‐b]quinazolin‐11‐one Using the Ullmann Condensation
作者:Rolando F. Pellón、Maite L. Docampo、Zulfia Kunakbaeva、Victoria Gómez、Herman Vélez‐Castro
DOI:10.1080/00397910500384566
日期:2006.3.1
Abstract The Ullmanncondensation between 2‐chlorobenzoic acid and 2‐amino‐6‐methyl pyridine in DMF as solvent yielded 2‐[(6‐methyl‐2‐pyridinyl)amino] benzoic acid. The cyclization of this acid gave two isomers, the 9‐methyl‐11H‐pyrido[2,1‐b]quinazolin‐11‐one and, in a minor quantity, 2‐methylbenzo[b][1,8]naphtyridin‐5(10H)‐one. Using ultrasound irradiation the pyridoquinazolin‐11‐one was obtained
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。