Copper-catalyzed aerobic aliphatic C–H oxygenation with hydroperoxides
作者:Pei Chui Too、Ya Lin Tnay、Shunsuke Chiba
DOI:10.3762/bjoc.9.138
日期:——
We report herein Cu-catalyzed aerobicoxygenation of aliphatic C-H bonds with hydroperoxides, which proceeds by 1,5-H radical shift of putative oxygen-centered radicals (O-radicals) derived from hydroperoxides followed by trapping of the resulting carbon-centered radicals with molecular oxygen.
Synthesis and Applications of Tetrahydrofuran-Stable Substituted (3-Lithioxyalkyl)- and (4-Lithioxyalkyl)lithiums, Modified with Magnesium 2-Ethoxyethoxide
作者:Ioannis D. Kostas、Constantinos G. Screttas
DOI:10.1021/jo9703010
日期:1997.8.1
Substituted hydroxyalkyl phenyl sulfides 3 have been synthesized from the corresponding allylic or homoallylic alcohols 2. Regiospecific cleavage of the C-SPh bond of the sulfides 3 by lithium dispersion in tetrahydrofuran (THF) led to the synthesis of substituted (3-lithioxyalkyl)- and (4-lithioxyalkyl)lithiums 4, most of which share the omega carbon with a carbocyclic ring. The organolithiums were modified with magnesium 2-ethoxyethoxide in order to suppress their reactivity toward THF cleavage, thus offering the advantage of preparing storable ethereal solutions of certain types of (lithioxyalkyl)lithiums. This strategy appears to be of rather broad scope. The functionalized organolithiums prepared in this way react normally with electrophilic reagents with yields in the range 35-55%. Thus, carboxylations of 4 yielded lactones 5, some of which are natural products, while reactions of 4 with benzophenone and cyclic ketones yielded 1,4- and 1,5-diols 6 and 7, respectively.
Synthesis and biological evaluation of substituted 2,2'-oxybis(propionic acid) derivatives and related compounds
作者:Gregory B. Bennett、William J. Houlihan、Robert B. Mason、Robert G. Engstrom