Active Metals from Potassium-Graphite. Iron-Graphite as a New Debrominating Agent of vic-Dibromoalkanes and of α-Bromo Ketones

Article abstract of DOI:10.1021/jo00344a024

Iron-graphite (Fe-Gr), easily prepared by reduction of FeCl3 with potassium-graphite (C8K) in tetrahydrofuran, is conveniently used for the stereospecific debromination of vic-dibromoalkanes to alkenes and for the reductive debromination of α-bromo ketones to ketones in high yields.The latter reaction proceeds via Fe(II) enolates, which undergo deuteration, condensation, or O-silylation by reaction respectively with D2O, heptanal, or chlorotrimethylsilane.Moreover, the reaction of α,α'-dibromo ketones with Fe-Gr leads to 2-oxyallyl cations which can be trapped by suitable electron-rich olefins (enamines) or dienes (furan).