As part of a comprehensive study of N-unsubstituted bispidines, the novel 9,9-difluorobispidine (D) has been synthesized. The compound crystallizes from pentane below 0 degrees C in the ordered-crystalline phase D-II and undergoes at 0-30 degrees C a stepwise endothermic phase transition to a dynamically disordered crystalline phase D-I; melting occurs at 227 degrees C. Single crystalline D-II has been subjected to X-ray structure analysis, revealing association of the molecules to form chains. Reaction of (1,5-hexadiene)PtCl2 with D affords {C7H10F2(NH)(2)}PtCl2 (D1), which can be converted by conventional routes to {C7H10F2(NH)(2)}Pt(cbdca)center dot 5H(2)O (D2) and {C7H10F2(NH)(2)}Pt(C2O4) (D3). Compound D1 crystallizes solvent-free from water and is isomorphous to the solvent-free parent bispidine analogue (A1). The pentahydrate D2 is isomorphous to the bispidine and 9-oxabispidine homologues (A2 and C2), as shown by X-ray structure analyses. An increased polarity of the bispidine skeleton as a consequence of the high electronegativity of fluorine is seen as the reason for low cytotoxic potency of D1-D3.