Fluorinations of ?-Seleno Carboxylic Acid Derivatives with Hypervalent (Difluoroiodo)toluene
作者:Maria A. Arrica、Thomas Wirth
DOI:10.1002/ejoc.200400659
日期:2005.1
A very efficient synthesis of (difluoroiodo)toluene avoiding the use of elemental chlorine and elemental fluorine is described. We have fluorinated a series of α-acceptor substituted selenides using (difluoroiodo)toluene.The reactions are usually very clean and under the reaction conditions no further oxidized products are observed.
S<sub>H<sup>2</sup></sub>REACTIONS OF SELENOSULFIDES WITH CARBON RADICALS
作者:Masato Yoshida、Toshitsura Cho、Michio Kobayashi
DOI:10.1246/cl.1984.1109
日期:1984.7.5
o-Nitrophenyl phenylselenyl sulfide suffered SH2 attack by carbon radicals on selenium atom to give selenide and thiyl radical; the relative rate constant of the selenosulfide with phenyl radical was compared with those of the other selenium compounds.
Several capto-dative olefins containing the phenylselenenyl group have been obtained via selenenyl halide addition to acrylic derivatives followed by halide elimination. Some of the olefins efficiently trap the radicals formed from azobisisobutyronitrile (AIBN) and methyl azobisisobutyrate (MAIB) to form intermediate bridged dehydrodimers, which spontaneously lose diphenyldiselenide to produce new
dimethylhydrazones 1 (R2=H) and derived from linear aliphatic aldehydes, has led to α-phenylselanyl hydrazones 2. α-Phenylselanyl nitriles 3 were, however, isolated when an excess of base and of PhSeX (X=Cl, Br) were used. Hydrazones 1 bearing an α-alkyl substituent (R2≠H) gave also nitriles 3. SAMP-hydrazones 4 showed the same reactivity and the corresponding nitriles 3 were obtained in a racemic form. The use of