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(η⁶-p-cymene)Cl₂]₂ yielded a diruthenium complex [Fe{C₅H₄P(C≡CH)₂}₂{RuCl₂(η⁶-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).

Graphical Abstract

Keywords:

• Ferrocenylbis(phosphine)
• alkynyl phosphine
• chelating
• metal complex
• crystal structure

Acknowledgement

We thank the Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, for instrumentation facilities, for spectral and analytical data.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

M.S.B. thanks Science and Engineering Research Board for funding this work through grant CRG/2019/000040.