Bicyclo[2.2.2]octane-2-spirocyclohexanes, Part 3 [1] Synthesis and Reactions of Mono- and Dibromospirodiisophoranes


H alogenation by the appropriate am ounts o f brom ine or N -brom osuccinim ide converts spirodiisophora-3 ',6-dione successively into the 4 '-ax-m onoand 2',4 '-diax-dibrom o-3',6-dione. The la tter is reduced by lithium alum inium hydride to the corresponding 6,3 '-ketol. with reten­ tion o f one or both brom o-substituents, depending on conditions. The… (More)