Allylic alkylation of co-ordinated cyanide; the synthesis and X-Ray crystal structure of trans-[Mn(CO)(CNCH2CMe = CH2)(dppm)2][PF6]·thf (dppm = Ph2PCH2PPh2, thf = tetrahydrofuran)

Abstract

The reaction of trans-[Mn(CN)(CO)(dppm)₂] with [Fe{P(OMe)₃}(NO)₂(η-C₃H₄R)][PF₆](R z. H, 1-Me, or 2-Me) in tetrahydrofuran (thf) results in allylic alkylation of the cyanide ligand to give the allyl isocyanide complexes trans-[Mn(CO)(CNCH₂CMeCH₂)(dppm)₂][PF₆]·thf and trans-[Mn(CO)(CNCH₂CHCHR)(dppm)₂][PF₆]·thf (RH or Me). The X-ray crystal structure of trans-[Mn(CO)(CNCH₂CMeCH₂)(dppm)₂][PF₆]·thf shows that in the cation the manganese(I) atom has approximately octahedral co-ordination, with the carbonyl and 2-methylallyl isocyanide ligands mutually trans, and the chelating dppm ligands occupying the four equatorial sites.