90879-06-4Relevant academic research and scientific papers
Palladium nanoparticlesin situsynthesized onCyclea barbatapectin as a heterogeneous catalyst for Heck coupling in water, the reduction of nitrophenols and alkynes
Le, Van-Dung,Le, T. Cam-Huong,Chau, Van-Trung,Le, T. Ngoc-Duyen,Dang, Chi-Hien,Vo, T. To-Nguyen,Nguyen, Trinh Duy,Nguyen, Thanh-Danh
, p. 4746 - 4755 (2021/03/22)
This study develops an effective method for thein situsynthesis of palladium nanoparticles (PdNPs) usingCyclea barbatapectin as a green reducing and stabilizing reagent. The PdNP@pectin nanocomposite was well characterized by analysis techniques such as UV-vis, FTIR, EDX, XRD, SEM, HR-TEM and STEM-mapping. Crystalline PdNPs were found to be distributed in the size range of 1-25 nm with the highest frequency of 6-12 nm. PdNP@pectin exhibited excellent recyclable catalysis activity for the Heck coupling reaction in water medium. The kinetics and recyclability of nanoparticles were investigated for the catalytic reduction ofo-,m- andp-nitrophenol. The result showed a good catalysis efficiency with five successful recycles without compromising much. In particular, the nanocomposite was used as a catalyst for the conversion of alkynes intocis-alkenes with KOH/DMF as a hydrogenation source. The reaction was also utilized effectively for the synthesis of sex pheromones, includingPlutella xylostella((Z)-11-hexadecen-1-yl acetate) andCylas formicarius((Z)-3-dodecen-1-yl(E)-2-butenoate) with the total yields of 70% and 68%, respectively. Therefore, PdNPs supported onC. barbatapectin are promising catalysis materials for application in various fields.
A convenient titanium-mediated intermolecular alkyne-carbonate coupling reaction
Wolan, Andrzej,Cadoret, Frédéric,Six, Yvan
experimental part, p. 7429 - 7439 (2009/12/06)
A direct diastereoselective titanium-mediated intermolecular coupling of internal alkynes with dialkyl carbonates under Kulinkovich-type reaction conditions is presented. The influence of the structures of the coupling partners on the yields and regioselectivities of this transformation is described.
Solvent-free carbon-oxygen bond formation catalysed by CeCl 3·7H2O/NaI: Tetrahydropyranylation of hydroxy groups
Bartoli, Giuseppe,Giovannini, Riccardo,Giuliani, Arianna,Marcantoni, Enrico,Massaccesi, Massimo,Melchiorre, Paolo,Paoletti, Melissa,Sambri, Letizia
, p. 1476 - 1482 (2007/10/03)
An efficient and highly chemoselective method fo the protection of free hydroxy compounds with 3,4-dihydro-2H-pyran is reported. Since the deprotection of THP-ethers occurs very readily at room temperature, the successful use of this type of protecting group depends only upon how readily it can be introduced. For this we have examined the tetrahydropyranylation of alcohols and phenols catalysed by the CeCl3·7H2O/NaI system surface under solvent-free conditions. The reaction presents the advantage of being performable under extremely mild conditions by use of catalytic amounts of an interesting Lewis acidic system consisting of the CeCl3· 7H2O/NaI catalyst combination, which can be easily separated from the reaction mixture. The advantages of this procedure, which utilizes cheap and "lfriendly" reagents, over the previously reported ones are discussed. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
COMPOUNDS WITH A HERBAL ODOR VI. THE E ISOMERS OF THE STRUCTURAL ANALOGS OF LEAF ALCOHOL
Vasil'ev, A. A.,Cherkaev, G. V.,Nikitina, M. A.
, p. 870 - 875 (2007/10/02)
The E isomers of leaf alcohol and its structural analogs differing in the length of the carbon chain, the presence of substituents at various positions of the molecule, the position of the double bond, and replacement of the double bond by a three-membered ring were synthesized.Many representatives of the Z and E series have a herbal odor, and similarity is observed in the odor of the respective pairs of Z and E isomers.The proximity of the odor of the investigated compounds to the standard (leaf alcohol) is determined by the number of carbon atoms in their molecules.
