Ligand-less palladium-catalyzed direct 5-arylation of thiophenes at low catalyst loadings

International audienc

Pyran-2-ones as synthons for pyridazine-3-carboxylic derivatives. Oxidation of nitrogen-rich compounds

Byla studována reakce 3-amino-6-(pyridin-2-yl)-2H-pyran-2-onu s N2H4.H2O s deriváty pyridazine. Ke zjištění reakčního mechanismu byl úspěšně izolován intermediárně vznikající ?,?-dihydrazonohydrazid. Popsány jsou také oxidace výše uvedených sloučenin a jiných derivátů pyridazinu obsahujících karbohydrazidovou skupinu dusičnanem ceričito-amonným (CAN), trihydrátem dusičnanu thallitého (TTN) nebo hydrátem octanu měďnatéhoThe reaction of 3-amino-6-(pyridin-2-yl)-2H-pyran-2-one with N2H4.H2O towards pyridazine derivs. was investigated. To elucidate the reaction pathway, an intermediary-formed ?,?-dihydrazono hydrazide was successfully isolated. Oxidns. of the above compds. as well as of other pyridazine derivs. contg. a carbohydrazido group, using cerium(IV) ammonium nitrate (CAN), thallium(III) nitrate trihydrate (TTN), or copper(II) acetate hydrate (CuDA), are also presented

Low Catalyst Loading Ligand-free Palladium-Catalyzed Direct Arylation of Furans: An Economically and Environmentally Attractive Access to 5-Arylfurans

International audienc

Ethynylene-analogues of hemicurcuminoids: Synthesis and ground- and excited properties of their boron difluoride complexes

International audienc