Reactions of cyano-iron and -ruthenium compounds with gem-dicyano-epoxides. A new pathway to vinyl isocyanide complexes of iron and ruthenium
The cyano complexes [M(CN)(cp)(dppe)](M = Fe or Ru, cp =η-C5H5, dppe = Ph2PCH2CH2PPh2) and the hydrogen isocyanide complex [Fe(cp)(dppe)(CNH)]Br reacted with gem-dicyano and gem-cyano(ethoxycarbonyl) epoxides to give oxazol-2-yl and oxazolin-2-ylidene complexes, respectively. Treatment of the oxazol-2-yl complexes with alkyloxonium salts, R3O+BF4–(R = Me or Et), resulted in ring opening to give multifunctional vinyl isocyanide complexes. The complexes were characterized by mass and NMR spectral techniques; in addition, a single-crystal structure determination was carried out on a vinyl isocyanide complex.