19820-47-4Relevant articles and documents
Regioselective Ortho‐C–H sulfenylation of free phenols catalyzed by Co(II)-immobilized on silica-coated magnetic nanoparticles
Khaef, Sepideh,Rostami, Abed,Khakyzadeh, Vahid,Zolfigol, Mohammad Ali,Taherpour, Avat Arman,Yarie, Meysam
, (2020/01/22)
Fe3O4?SiO2-UT?CoII is prepared by the silica-coated magnetic nanoparticles, urea-triazole, and CoCl2. This organic-inorganic hybride composite showed a good to excellent catalytic activity toward regioselective ortho-sulfenylation of free phenols and naphthols using pivalic anhydride as a directing group, also K2S2O8 and PPh3 were employed as oxidant and additive respectively. The newly synthesized catalyst was fully characterized by using different techniques such as FT-IR, TGA, DTG, TEM, SEM, EDS, ICP and VSM analyses. The competitive price, accessibility and lower toxicity of cobalt compared to expensive transition metals using for C–H bond activation and functionalization constitute precious advantages for this method. Moreover, this heterogeneous catalyst could be magnetically recovered and reused without significant loss of its catalytic activity after five cycles.
Copper-Mediated Functionalization of Aryl Trifluoroborates
Schimler, Sydonie D.,Sanford, Melanie S.
supporting information, p. 2279 - 2284 (2016/10/06)
This paper describes the Cu(OTf)2-mediated coupling of aryl and heteroaryl trifluoroborates with tetrabutylammonium or alkali metal salts to form C-O, C-N, and C-halogen bonds. The reactions proceed under mild conditions (often room temperature over 16 hours) with carboxylate, halide, and azide salts, all nucleophiles that have been underrepresented in the copper cross-coupling literature. Preliminary results show that copper salts bearing weakly coordinating X-type ligands are essential for enabling these transformations to proceed under mild conditions.
A New and Efficient Esterification Reaction via Mixed Anhydrides by the Promotion of a Catalytic Amount of Lewis Acid
Miyashita, Mitsutomo,Shiina, Isamu,Miyoshi, So,Mukaiyama, Teruaki
, p. 1516 - 1527 (2007/10/02)
In the presence of a catalytic amount of Lewis acid, various carboxylic esters or S-phenyl carbothioates are prepared in excellent yields by the respective reactions of equimolar amounts of silyl carboxylates and alkyl silyl ethers or phenyl silyl sulfides with 4-trifluoromethylbenzoic anhydride.
