52792-18-4Relevant academic research and scientific papers
Synthesis and photoluminescent properties of conjugated aryl-vinyl dioctyl 2,6-dimethylbenzofuro[5,6-b]furan-3,7-dicarboxylate derivatives
Bosiak, Mariusz J.,Rakowiecki, Marcin,Or?owska, Katarzyna J.,K?dziera, Dariusz,Adams, J?rg
, p. 803 - 811 (2013)
The synthesis of highly fluorescent conjugated benzodifuran aryl-vinyl systems, containing four double bonds and at least four phenyl rings, is described. The ethyl groups of diethyl 2,6-dimethylbenzofuro[5,6-b]furan-3,7- dicarboxylate, obtained by the Michael type condensation of p-benzoquinone and ethyl acetoacetate, were replaced by octyl groups via the transesterification reaction to improve the desired product solubility in common organic solvents. The dioctyl ester was brominated and used for the Wittig reaction with stilbene aldehydes, obtained by the Heck reaction of 4-bromobenzaldehyde and an appropriate styrene. The products, obtained in 48-92% yield, exhibit the UV-Vis fluorescence with high quantum yields, 58-69%.
SYNTHESES OF METAL HETEROCYCLIC CARBENE ENOLATES AS COUPLING REACTIONS CATALYSTS
-
Page/Page column 15; 18; 31, (2017/07/01)
The invention relates to the synthesis methods of N-heterocyclic carbene NHCE metal complexes and their catalytic activities in carbon-carbon coupling reactions.
Novel stilbene-based Fischer base analog of leuco-TAM - (2E,2′Z)-{2-(4-(E)-styrylphenyl)propane-1,3-diylidene}bis(1,3,3-trimethylindoline) - derivatives: Synthesis and structural consideration by 1D NMR and 2D NMR spectroscopy
Keum, Sam-Rok,Lim, Hyun-Woo
, p. 143 - 150 (2016/02/09)
We report the synthesis of a series of novel stilbene-based (St) Fischer base analogs of leuco-triarylmethane (LTAM) dyes by treating Fischer base with (E)-4-styrylbenzaldehyde derivatives. All St-LTAM molecules examined herein are characterized by 1D and 2D NMR. They were found to exhibit ZE configuration and isomerize to their diastereomers EE and ZZ in 2-3 h. They exhibit type I behavior of diastereomeric isomerization.
Water mediated Heck and Ullmann couplings by supported palladium nanoparticles: Importance of surface polarity of the carbon spheres
Kamal, Ahmed,Srinivasulu, Vunnam,Seshadri,Markandeya, Nagula,Alarifi,Shankaraiah, Nagula
, p. 2513 - 2522 (2013/02/21)
Heterogeneous palladium nanoparticle catalysts that are supported on amphiphilic carbon spheres (Pd@CSP) have been utilized for water-mediated Heck coupling reactions of aryl halides with different alkenes under phosphine free as well as aerobic conditions. Furthermore, a variety of Heck coupling reactions using different bases and solvents, including organic polar and non-polar solvents, have been explored. Aryl bromides are also well activated in Heck coupling reactions in organic polar solvent and as well as in water. In addition, Ullmann coupling reactions of aryl iodides have been catalyzed in water with the aid of phase transfer catalysts (PTC) in moderate yields. A plausible mechanism for the catalytic activity of Pd@CSP in the case of the Ullmann reaction is also established. It has been demonstrated that the hydrophobic effects of the catalyst surface play an important role in catalyst activity in water. In addition, the E-factor analysis verified that our present protocol is significantly comparable with other catalytic systems and explains the improved greenness. Moreover, the catalyst described in this process is not only greener, but also retains its significant activity for up to four catalytic cycles for the Heck coupling reactions. The surface polarity of the amphiphilic carbon spheres results in higher activity under these conditions.
Palladium chloride and tetraphenylphosphonium bromide intercalated clay as a new catalyst for the Heck reaction
Varma, Rajender S.,Naicker, Kannan P.,Liesen, Per J.
, p. 2075 - 2078 (2007/10/03)
A new modified clay material, prepared by intercalating palladium chloride and tetraphenylphosphonium bromide into montmorillonite K10 clay, catalyzes the Heck reaction and affords trans-stilbenes in high yields.
