Rhodium(III)-Catalyzed Regioselective Decarboxylative Cyclization for the Synthesis of 4<i>H</i>-Furo[3,2-<i>c</i>]chromen-4-one Derivatives
作者:Dandan Zha、Hongji Li、Shiqing Li、Lei Wang
DOI:10.1002/adsc.201600974
日期:2017.2.2
This contribution describes a regioselective cyclization of hypervalent iodine reagents (HIR) with propiolic acids in the presence of a rhodium catalyst. The mild decarboxylation can tolerate a wide range of groups and generates 4H‐furo[3,2‐c]chromen‐4‐one derivatives in good isolated yields.
该贡献描述了在铑催化剂存在下用丙酸对高价碘试剂(HIR)的区域选择性环化。轻度的脱羧可以耐受广泛的基团,并以良好的分离产率生成4 H-呋喃[3,2 - c ] chromen-4-one衍生物。
FeCl<sub>3</sub>/ZnI<sub>2</sub>-Catalyzed regioselective synthesis of angularly fused furans
作者:Amrita Dey、Alakananda Hajra
DOI:10.1039/c7ob02124k
日期:——
The FeCl3/ZnI2-catalyzed synthesis of angularly fused furans by intermolecular coupling between enols and alkynes has been developed in ambient air. The methodology is successfully applicable to 4-hydroxycoumarin, 4-hydroxyquinolinone and α-tetralone affording regioselective 2-aryl furans in good yields. The control experiments suggest the possibility of a radical reaction mechanism.
Furans Accessed through Visible-Light-Mediated Oxidative [3+2] Cycloaddition of Enols and Alkynes
作者:Ailong Shao、Xu Luo、Chien-Wei Chiang、Meng Gao、Aiwen Lei
DOI:10.1002/chem.201704519
日期:2017.12.19
Visible‐light‐mediated formation of furans though direct oxidative [3+2] cycloaddition of 1,3‐diones and alkynes is described. This protocol provides a simple and mild route to poly‐substituted furans in moderate‐to‐good yields. Preliminary mechanistic studies suggest that this reaction likely follows a radical addition/cyclization pathway.
A novel and efficient procedure for the synthesis of furo[3,2-c]coumarins from readily available 4-oxohydrocoumarins and alkenes in the presence of a catalytic amount of Pd(CF3COO)2 has been developed.
The synthesis of privileged structures, which are potent drug candidates, is an impetus for drug discovery. The construction of heterocyclic framework furo[3,2-c]coumarins using a visible-light promoted photoredox neutral coupling of 3-bromo-4-hydroxycoumarins with commercially available alkynes has been reported. These reactions can be carried out at room temperature under visible light irradiation
作为潜在药物候选者的特权结构的合成是药物发现的动力。已经报道了使用3-溴-4-羟基香豆素与市售炔烃的可见光促进的光氧化还原中性偶联来构建杂环骨架呋喃[3,2- c ]香豆素。这些反应可以在室温下在可见光照射下以良好的化学产率进行。这项工作提出了17种呋喃香豆素,其中12种是新的。新合成的化合物中的三种显示出有效的细胞毒性,一种显示出中等的乙酰胆碱酯酶抑制活性,IC 50值为2.16±0.13μM。