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...
Pyrido[2,1-b]quinazolinecarboxylic acids as orally active antiallergy agents
作者:Jefferson W. Tilley、Ronald A. LeMahieu、Mathew Carson、Richard W. Kierstead、Herman W. Baruth、Bohdan Yaremko
DOI:10.1021/jm00175a020
日期:1980.1
A series of 8-substituted pyrido[2,1-]quinazoline-2-carboxylic acids was prepared by the nickel carbonyl mediated carboxylation of the corresponding bromides. The activities of these compounds in the rat PCA test are comparable to those of the corresponding 2-substituted pyrido[2,1-b]quinazoline-8-carboxylic acids.
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
autoclave‐free protocol for the synthesis of 11H‐pyrido[2,1‐b]quinazolin‐11‐ones has been developed. Quinazolinones, which are omnipresent motif in many pharmaceuticals and agrochemicals, were prepared in good yields by CH bond activation and annulation using DMF as the CO surrogate. A 13CO‐labelled DMF control experiment demonstrated that CO gas was released from the carbonyl of DMF with acid as
为11的合成一种新型的钯催化CO-气体和无高压釜协议ħ -吡啶并[2,1- b ]喹唑啉-11-那些已经研制成功。喹唑啉酮是许多药物和农用化学品中无处不在的基序,它是通过CH键活化和使用DMF作为CO替代物进行环化而制备的,产率很高。一项13 CO标记的DMF对照实验表明,以酸为促进剂从DMF的羰基中释放出CO气体。的动力学同位素效应(KIE)值指示,在C ħ活化步骤可以不是在速率决定步骤有关。该方法操作简单,显示了广泛的底物范围,具有良好至极好的产率。