The bis-1,4-dimesityl-1,2,3-triazol-5-ylidene–palladium complex (1a) successfully catalyzes the Mizoroki–Heck and Sonogashira coupling reactions with aryl bromides to give the corresponding alkenes and alkynes, respectively, in good to excellent yields. In the Mizoroki–Heck reaction, electron-rich, electron-poor, and functionalized aryl bromides and alkenes are tolerated, while the substrates are limited
A new polystyrene supported thiopseudourea palladium(II) complex (3) is found to be a highly active catalyst for the copper-free Sonogashira, Suzuki, Heck, Hiyama and Larock heteroannulation reactions of arylhalides. All the reactions proceeded well affording the corresponding cross-coupling products in good to excellent yields. Further, the catalyst showed excellent recyclability without any significant
<i>o</i>-Iodoxybenzoic acid mediated generation of aryl free radicals: synthesis of stilbenes through C–C cross-coupling with β-nitrostyrenes
作者:Ganesh Wagh、Snehalata Autade、Pravin C. Patil、Krishnacharya G. Akamanchi
DOI:10.1039/c7nj04701k
日期:——
substrate scope and transitionmetalfree, mild reaction conditions, under an open atmosphere in a short reaction time. A free radical mediated mechanism was postulated and supported by radical trapping experiments. Application of the developed methodology is demonstrated through a simple, two step synthesis of resveratrol, a valuable stilbenoid for anticancer and neurological studies via its prodrug E-1,
Lipids as versatile solvents for chemical synthesis
作者:Ashot Gevorgyan、Kathrin H. Hopmann、Annette Bayer
DOI:10.1039/d1gc02311j
日期:——
Development of safe, renewable, cheap and versatile solvents is a longstanding challenge in chemistry. We show here that vegetable oils and related systems can become prominent solvents for organic synthesis. Suzuki–Miyaura, Hiyama, Stille, Sonogashira and Heck cross-couplings proceed with quantitative yields in a range of vegetable oils, fish oil, butter and waxes used as solvents. Appropriate methodologies
NNN pincer palladium(II) complexes with N-(2-(1H-pyrazol-1-yl)phenyl)-picolinamide ligands: synthesis, characterization, and application to heck coupling reaction
picolinamide ligands 3a–c and 5a–f have been easily prepared from commercially available 2-pyridinecarboxylic acid. Reaction of 3a–c and 5a–f with PdCl2 in toluene in the presence of triethylamine gave the nine NNN pincer Pd(II) complexes 6a–i in 15–91% yields. All the new compounds were characterized by 1H, 13C NMR spectra and HRMS. In addition, the molecular structures of complexes 6a and 6i have