The scope and limitations of the bis-trifluoromethylation was examined next (Figure ). The reaction was successfully applied to different cyclic ketone-derived alkylidenemalononitrile substrates. For example, prepared were bis-trifluoromethylated-N-Boc-piperidine (3b), thiopyran (3c), and cyclohexanes bearing ketal (3d), ditrifluoromethylene (3e), and ester (3f) functional groups. We also The ester-and 2-methyl-piperidyl products (3f and 3g) present additional diastereoselective considerations. While prepared as single diastereomers, the relative stereochemistry at the ester-(3f) and the methyl-(3g) were not determined in this study. Regarding limitations, it appears that this particular optimized protocol for bis-trifluoromethylation is potentially intolerant to gamma-substitution with respect to the alkylidenemalononitrile group. Upon reaction with substrate 1h, derived from 3-methyl-N-boc-piperidone, only decomposition was observed. Similarly, an acyclic substrate 1i also resulted in decomposition.