Enantioselective Synthesis of Bicyclo[4.4.1]undecane-2,7-dione via Samarium(II)-Mediated Fragmentation of a Cyclopropane Precursor - El Sheikh, Sherif; Kausch, Nina; Lex, J; Neudörfl, J -M; Schmalz, Hans-Günther (Synlett, 2006)