通过3-(邻甲氧基苯基)-1,2-二氢喹啉-2-酮(VIa,b)的脱甲基环化反应合成苯并呋喃[2,3- b ]喹啉(Ia)及其11-甲基衍生物(Ib)。苯并呋喃[2,3 - b ]喹啉-11-羧酸(Id)通过氯化反应,然后通过3-(邻甲氧基苯基)-2-的甲基环化反应制得的内酯(IX)的氢氧化钾作用合成氧代1,2-二氢喹啉-4-羧酸(VIII)。异构苯并呋喃[3,2-c]喹啉(Ha)及其6-甲基衍生物(IIb)是通过3-(o-甲氧基苯基)-1,4-二氢喹啉-4-酮(XIa,b)。通过与苯甲醛缩合,然后氧化,将两种甲基衍生物(Ib和IIb)都转化为羧酸(Id和IId)。由此获得的苯并呋喃喹啉(Ia,b,d和IIa,b)被氧化成相应的N-氧化物(IIIa,b,d和IVa,b)。
Iminyl radicals are reactive intermediates that can be used for the construction of various valuable heterocycles. Herein, the electrochemical decarboxylation of α-imino-oxy acids for the generation of iminyl radicals has been accomplished under exogenous-oxidant- and metal-free conditions through the use of nBu4NBr as a mediator. The resulting iminyl radicals undergo intramolecular cyclization smoothly
亚胺基是反应性中间体,可用于构建各种有价值的杂环。在此,通过使用n Bu 4 NBr 作为介体,在无外源氧化剂和无金属条件下完成了用于产生亚胺基自由基的 α-亚氨基-羟基酸的电化学脱羧。所得亚胺基自由基与相邻的(杂)芳烃顺利进行分子内环化,得到一系列吲哚稠合的多环化合物。
Synthesis of Benzofuroquinolines via Phosphine-Free Direct Arylation of 4-Phenoxyquinolines in Air
作者:Rachel M. Shanahan、Aobha Hickey、F. Jerry Reen、Fergal O'Gara、Gerard P. McGlacken
DOI:10.1002/ejoc.201800923
日期:2018.12.2
A palladium‐catalysed, phosphine‐free, directarylation of 4‐phenoxyquinolines in air is described. Using intramolecular directarylation, the ring‐closed products are formed in isolated yields of up to 95 %. This approach allows access to a range of benzofuroquinolines, and an array of functional groups on both the quinoline and phenoxy rings is tolerated.
The example of palladium-catalyzed intermolecular cyclization for the synthesis of various diarylfurans in which one of the aromatic rings originates from the phenolic part of the starting ester and the other one from PhI(OAc)2 has been reported. The reaction is carried out through two steps: the rearrangement of palladium-associated iodonium ylides to form o-iodo diaryl ether and then palladium catalyzed
Cu‐catalyzed dehydrogenative CO arylation for the synthesis of 6‐methyl benzofuro[3,2‐<scp><i>c</i></scp>] quinoline derivatives
作者:Bhavik S. Makwana、Mayur I. Morja、Prakashsingh M. Chauhan、Kishor H. Chikhalia
DOI:10.1002/jhet.4774
日期:2024.3
for the synthesis of 6-methyl benzofuro[3,2-c] quinolinederivatives via copper-catalyzed dehydrogenative CO arylation has been presented. Optimization studies have been carried out by varying various catalysts, bases, solvents, and other physical parameters. Keeping use of this dehydrogenative cross-coupling CO arylation reaction, a variety of bioactive building blocks like fused benzofuro quinoline
提出了一种通过铜催化脱氢C - O芳基化合成6-甲基苯并呋喃并[3,2- c ]喹啉衍生物的新策略。通过改变各种催化剂、碱、溶剂和其他物理参数进行了优化研究。继续利用这种脱氢交叉偶联C → O芳基化反应,各种生物活性结构单元(例如稠合苯并呋喃喹啉杂环)能够以中等至较高的产率顺利组装。
Regioselective Partial Hydrogenation and Deuteration of Tetracyclic (Hetero)aromatic Systems Using a Simple Heterogeneous Catalyst
作者:Roberta A. Kehoe、Amy Lowry、Mark E. Light、David J. Jones、Peter A. Byrne、Gerard P. McGlacken
DOI:10.1002/chem.202400102
日期:2024.3.20
‘3-dimensionality’ through late-stage functionalisation is a powerful synthetic approach to biologically significant moieties. Herein, a hydrogenative, regioselective dearomatisation of extended (hetero)aromatic systems is described, using a simple Pd catalyst at atmospheric hydrogen pressure. Deuteration is also demonstrated and some initial mechanistic insights are revealed.