Using Me3Si-F-Al(OR F)3 and Me3Si-Cl as Methylating Agents - Synthesis and Characterization of SeMeCl2[F{Al(OR F)3}2]: Using Me3Si-F-Al(OR F)3 and Me3Si-Cl as Methylating Agents - Synthesis and Characterization of SeMeCl2[F{Al(OR F)3}2]