Tsuji-Wacker oxidation of alkene 10 into ketone 11 proceeded in excellent yield using PdCl2/CuCl in aqueous DMF (Figure ). We made many attempts to crystallize 11, but, in most cases, we were unsuccessful. In one instance, high quality crystals formed from slow evaporation from acetone in a scintillation vial open to air (~14 days). However, to our surprise, the crystals were of imine 12, which we hypothesize formed from slow oxidation of 11.