Piperidine derivatives usually have a significant biological activity. This study is divided into three themes: (1) BF3–OEt2 promoted synthesis of spiroindenyl heterocycles. (2) N-bromosuccinimide promote rearrangment of 4-diarylmethylene piperidines. (3) Nucleophilic substitution studies of 3-diarylmethylene piperidines by trimethylsilyl-catalyst (TMS-Y). These novel synthetic methods are more direct and rapid synthetic approches to the piperidine skeletons.