A practical method for the selective and controlled oxidation of thioglycosides to corresponding glycosyl sulfoxides and sulfones is reported using urea-hydrogen peroxide (UHP). A wide range of glycosyl sulfoxides are selectively achieved using 1.5 equiv of UHP at 60 °C while corresponding sulfones are achieved using 2.5 equiv of UHP at 80 °C in acetic acid. Remarkably, oxidation susceptible olefin
A facile and selective oxidation of sulfides to sulfones
作者:Waldemar Priebe、Grzegorz Grynkiewicz
DOI:10.1016/0040-4039(91)80105-f
日期:1991.12
Sulfides undergo a facile and selective oxidation to sulfones under mild conditions using a catalytic amount of osmium tetroxide and tertiary amineN-oxides (N-methylmorpholine N-oxide or trimethylamineN-oxide). Both N-oxides are equally effective. The observed yields ranged between 60%–95%.
Radical dimerization of glycosyl 2-pyridylsulfones with samarium (II) iodide in the presence of HMPA
作者:Gilles Doisneau、Jean-Marie Beau
DOI:10.1016/s0040-4039(98)00568-1
日期:1998.5
Reduction of glycosyl 2-pyridylsulfones by samarium (II) iodide in the presence of HMPA leads to glycosyl dimers in up to 74% yield. This is rationalized by a free-radical mechanism.
Reductive elimination of glycosyl phenyl sulfones by SmI2-HMPA: A convenient synthesis of substituted pyranoid glycals
作者:Pierre de Pouilly、Alain Chénedé、Jean-Maurice Mallet、Pierre Sinaÿ
DOI:10.1016/s0040-4039(00)74718-6
日期:1992.12
A series of substituted glycosyl phenyl sulfones was converted into glycals after reductive samariation with SmI2 in the presence of hexamethylphosphoric triamide, followed by elimination of the substituent at C-2. Practically quantitative yields were obtained when the leaving group was an acetate, as illustrated here with seven substrates.