100560-75-6Relevant academic research and scientific papers
Co-Cluster-Based Metal–Organic Frameworks as Selective Catalysts for Benzene Tandem Acylation–Nazarov Cyclization to Benzocyclopentanone
Liu, Mengjia,Gao, Kuan,Fan, Yanru,Guo, Xiaoqing,Wu, Jie,Meng, Xiangru,Hou, Hongwei
, p. 1416 - 1424 (2018)
One-step selective benzene acylation–Nazarov cyclization is an attractive, yet challenging method for the synthesis of the benzocyclopentanone skeleton, which is key intermediate of many natural products. Herein, two metal-cluster-based metal–organic frameworks (MCOFs) {(H3O)2[Co4(pbcd)2(μ3-OH)2]?CH3CH2OH?4 H2O}n (1; pbcd=9,9′-(propan-1,3-diyl)bis(9H-carbazole-3,6-dicarboxylic acid) and {[Co5.25(mcd)2(HCO2)(μ2-O)0.5(μ3-OH)0.5(H2O)4]?6 H2O?5 DMF}n (2; mcd=9,9′-methylenebis(9H-carbazole-3,6-dicarboxylic acid) were developed to catalyze a tandem Nazarov cyclization reaction of 1,3-dimethoxybenzene with α,β-unsaturated carboxylic acids for the synthesis of cyclopentenone[b]benzenes. MCOFs 1 and 2, which were constructed from tetranuclear CoII cluster [Co4(μ3-OH)2] and hexanuclear CoII cluster [Co6(HCO2)(μ2-O)(μ3-OH)], respectively, exhibit high catalytic activity arising not only from their suitable channel size and accessible catalytic sites, but also because of their high density of Lewis acidic sites within the frameworks and the synergic activity among CoII ions. In contrast, {[Co2(pbcd)(bpe)]?2 H2O?2 DMF}n (3; bpe=1,2-bis(pyridin-4-yl)ethane) containing binuclear CoII and having large pore windows is a highly selective catalyst for obtaining exclusively the acylation products. Easy product separation, simple reaction procedures, and catalyst recycling make the catalyst system attractive. This work highlights the synergistic effect among ions of MCOFs in interacting with substrates in a sequential or cooperative manner to achieve tandem catalysis.
POLYGONOLIDE, AN ISOCOUMARIN FROM POLYGONUM HYDROPIPER POSSESSING ANTI-INFLAMMATORY ACTIVITY
Furuta, Takuya,Fukuyama, Yoshiyasu,Asakawa, Yoshinori
, p. 517 - 520 (2007/10/02)
Key Word Index-Polygonum hydropiper; Polygonaceae; polygonolide; 3,4-dimethyl-6-methoxy-8-hydroxyisocoumarin; synthesis; anti-inflammatory reaction.A new isocoumarin polygonolide which inhibits the reversed passive Arthus reaction has been isolated from t
The Synthesis of Indan-1-ones and Isocoumarins
Carter, Rachel H.,Garson, Mary J.,Hill, Robert A.,Staunton, James,Sunter, David C.
, p. 471 - 479 (2007/10/02)
A flexible synthetic route leading via indan-1-ones to variously methylated and oxygenated isocoumarins is described.The indanones are prepared by alternative routes involving intramolecular Friedel-Crafts cyclisation of arylpropionic acids or pericyclic ring closure of acrylophenones.The influence of substitution on the rate of the pericyclic reaction is assessed.
