Organonitrile complexes of iron(II) and Ruthenium(II): X-ray crystal structure of trans-[Fe(NCMe)2(dmpe)2](BPh4)2

Abstract

The interaction of FeCl2(dmpe)2 [dmpe = 1,2-bis(dimethylphosphino)ethane] with RCN (R = Me or Et) gives the partially substituted complex trans-[FeCl(NCR)(dmpe)2]Cl at room temperature, but in refluxing RCN in the presence of NaBPh4 the product is trans-[Fe(NCR)2(dmpe)2](BPh4)2. The X-ray crystal structure of the acetonitrile complex has been determined. No reaction is observed between RuCl2(dmpe)2 and MeCN, although the disubstituted complex can be made in a similar way to the iron analogue. The interaction of trans-[M(NCMe)2(dmpe)2][BPh4)2 (M = Fe or Ru) with H2 leads to the amine complexes trans-[M(H2NEt)2(dmpe)2](BPh4)2. Although the ethylamine can be removed on refluxing in MeCN the complexes do not act as catalysts. Addition of MeCN to FeCl2(PMe3)2 yields only the complex [FeCl(NCMe)(PMe3)2]Cl; RuCl2(PMe3)4 reacts in refluxing MeCN in the presence of NaBPh4 to give trans-[Ru(NCMe)2(PMe3)4](BPh4)2.