38695-36-2Relevant academic research and scientific papers
Novel Carbazole-Based N-Heterocyclic Carbene Ligands to Access Synthetically Relevant Stilbenes in Pd-Catalyzed Coupling Processes
Girase, Tejpalsingh Ramsingh,Kapdi, Anant R.
supporting information, p. 2611 - 2619 (2019/07/05)
A series of new carbazole-based N-heterocyclic carbene (NHC) ligands have been synthesized in a simple and facile synthetic route and subsequently used in a Pd/carbazole-based NHC catalytic system, which was found to be effective in catalyzing Heck reactions to provide substituted stilbene derivatives in good yields. Several bioactive stilbenes, including pterostilbene, pinosylvin, trimethoxy resveratrol, and resveratrol, were synthesized in good yields, and a 10 mmol scale-up was also performed for trimethoxy resveratrol. The synthetic application was also extended by performing a double-tandem chemoselective Heck reaction followed by Miyaura borylation in a one-pot procedure to give single-step access to synthetically useful stilbenyl boronate esters. Similarly, a unique triple-tandem protocol of a chemoselective Heck reaction/Miyaura borylation/Suzuki–Miyaura coupling reaction sequence was performed for the one-pot modification of biologically relevant molecules.
Ligand-controlled iridium-catalyzed semihydrogenation of alkynes with ethanol: highly stereoselective synthesis of E- and Z-alkenes
Yang., Jinfei,Wang, Chengniu,Sun, Yufeng,Man, Xuyan,Li, Jinxia,Sun, Fei
supporting information, p. 1903 - 1906 (2019/05/02)
A ligand-controlled iridium-catalyzed semihydrogenation of alkynes to E- and Z-alkenes with ethanol was developed. Effective selectivity control was achieved by ligand regulation. The use of 1,2-bis(diphenylphosphino)ethane (DPPE) and 1,5-cyclooctadiene (COD) was critical for the stereoselective semihydrogenation of alkynes. The general applicability of this procedure was highlighted by the synthesis of more than 40 alkenes, with good stereoselectivities. The value of our approach in practical applications was investigated by studying the effects of pinosylvin and 4,4′-dihydroxystilbene (DHS) on zebrafish as a vertebrate model.
Functionalized β-cyclodextrin as supramolecular ligand and their Pd(OAc)2 complex: Highly efficient and reusable catalyst for Mizoroki-Heck cross-coupling reactions in aqueous medium
Dindulkar, Someshwar D.,Jeong, Daham,Kim, Hwanhee,Jung, Seunho
, p. 85 - 94 (2016/06/01)
A novel class of water soluble palladium complexes with recognition abilities based on functionalized β-cyclodextrin has been synthesized. The complex demonstrated high catalytic activity and a supramolecular platform for phosphine-free Mizoroki-Heck cross-coupling reactions in water. The efficient arylation of alkenes was carried out using different iodo- and bromo-arenes with good to excellent yields (up to 96%). The advantages, like recyclability of catalysts, operational simplicity and accessibility in aqueous medium, make this protocol eco-friendly.
Stereoselective peterson olefinations from bench-stable reagents and N-phenyl imines
Das, Manas,Manvar, Atul,Jacolot, Ma?wenn,Blangetti, Marco,Jones, Roderick C.,O'Shea, Donal F.
, p. 8737 - 8740 (2015/06/08)
The synthesis of bench-stable α,α-bis(trimethylsilyl)toluenes and tris(trimethylsilyl)methane is described and their use in stereoselective Peterson olefinations has been achieved with a wide substrate scope. Product stereoselectivity was poor with carbonyl electrophiles (E/Z ～1:1 to 4:1) though this was significantly improved by employing the corresponding substituted N-benzylideneaniline (up to 99:1) as an alternative electrophile. The olefination byproduct was identified as N,N-bis(trimethylsilyl)aniline and could be easily separated from product by aqueous acid extraction. Evidence for an autocatalytic cycle has been obtained.
Arenediazonium salts immobilized in imidazolium ionic liquids as electrophilic partners in the Pd(OAc)2-catalyzed Matsuda-Heck arylation
Kalkhambkar, Rajesh G.,Laali, Kenneth K.
experimental part, p. 1733 - 1737 (2011/05/05)
The utility of arenediazonium salts immobilized in imidazolium-ILs [BMIMPF6 and BMIMBF4] for facile, high yielding, synthesis of olefins via the Pd(OAc)2-catalyzed Matsuda-Heck arylation reaction has been demonstrated. The reaction can also be performed as a two-step process in the IL starting from ArNH2, by sequential in-situ diazotization-arylation. Simple product isolation and the recycling/re-use of the IL are additional advantages of this one-pot method.
Spectroscopic Correlations between Supermolecules and Molecules. Anatomy of the Ion-Modulated Electronic Properties of the Nitrogen Donor in Monoazacrown-Derived Intrinsic Fluoroionophores
Yang, Jye-Shane,Hwang, Chung-Yu,Hsieh, Chia-Chun,Chiou, Shih-Yi
, p. 719 - 726 (2007/10/03)
The synthesis, absorption and emission spectra, fluorescence quantum yields, and fluorescence lifetimes of three compound series of trans-4,4′-disubstituted aminostilbenes (1-3) are reported. The chromo-/fluoroionophoric behavior of the monoaza-15-crown-5
