Platinum (II) complexes featuring chiral diphosphines and N-heterocyclic carbene ligands: synthesis and evaluation as cycloisomerization catalysts

D. Brissy (1) , M. Skander (1) , P. Retailleau (1) , Gilles Frison (2) , Angela Marinetti (1)

1 ICSN - Institut de Chimie des Substances Naturelles
2 DCMR - Laboratoire des mécanismes réactionnels

Square-planar platinum(II) complexes that combine chiral diphosphines and NHC ligands have been obtained in high yields from (NHC)Pt(0)(dvtms) complexes, via an oxidative addition/ligand exchange sequence. The use of suitable carbene−diphosphine pairs allows axially chiral, configurationally stable platinum complexes to be isolated. The Pt(II) complexes have been evaluated as precatalysts for the cycloisomerization reaction of an allyl propargylamine derivative. Their catalytic properties have been examined as a function of structural variations on both the diphosphine and the NHC units. For axially chiral species possible epimerization pathways have been envisioned and the inversion barriers have been estimated through computational studies

Domaines: Chimie organique; Chimie théorique et/ou physique; Chimie de coordination; Chimie inorganique

D. Brissy, M. Skander, P. Retailleau, Gilles Frison, Angela Marinetti. Platinum (II) complexes featuring chiral diphosphines and N-heterocyclic carbene ligands: synthesis and evaluation as cycloisomerization catalysts. Organometallics, 2009, 28 (1), pp.140-151. ⟨10.1021/om800743r⟩. ⟨hal-00365790⟩