Synthesis, reactivity and transition metal complexes of 1,1′-bis(diethynylphosphino)ferrocene

Abstract

The synthesis, oxidation reactions and transition metal complexes of a new ferrocenyl-bisphosphine, [Fe{C5H4P(C≡CH)2}2] (1), are described. The reaction of bis(dichlorophosphino)ferrocene with four equivalents of ethynylmagnesium bromide resulted in the formation of 1 in 76% yield. The reaction between 1, aqueous H2O2 or elemental sulphur produced bis(oxide) and bis(sulfide) derivatives, [Fe{C5H4P(E)(C≡CH)2}2] (2 E = O, 3 E = S). Reaction of 1 with [Ru(η 6-p-cymene)Cl2]2 yielded a diruthenium complex [Fe{C5H4P(C≡CH)2}2{RuCl2(η 6-p-cymene)}2] (4). Treatment of 1 with [M(COD)Cl2] (M = Pd, Pt) resulted in [Fe{C5H4P(C≡CH)2}2{MCl2}] (5 M = Pd, 6 M = Pt). Equimolar reactions between 1 and CuX produced binuclear complexes, [Fe{C5H4P(C≡CH)2}2{CuX}2] (7 X = Cl, 8 X = Br, 9 X = I).