Cationic Tetrylene‐Iron(0) Complexes: Access Points for Cooperative, Reversible Bond Activation and Open‐Shell Iron(−I) Ferrato‐Tetrylenes**
Philip M. Keil, Ademola Soyemi, Kilian Weißer, Tibor Szilvási, Christian Limberg, Terrance J. Hadlington
Abstract
Abstract The open‐shell cationic stannylene‐iron(0) complex 4 ( 4 =[ PhiP DippSn⋅Fe⋅IPr] + ; PhiP Dipp={[Ph 2 PCH 2 Si( i Pr) 2 ](Dipp)N}; Dipp=2,6‐ i Pr 2 C 6 H 3 ; IPr=[(Dipp)NC(H)] 2 C:) cooperatively and reversibly cleaves dihydrogen at the Sn−Fe interface under mild conditions (1.5 bar, 298 K), in forming bridging hydrido‐complex 6 . The One‐electron oreduction of the related Ge II −Fe 0 complex 3 leads to oxidative addition of one C−P linkage of the PhiP Dipp ligand in an intermediary Fe −I complex, leading to Fe I phosphide species 7 . One‐electron reduction reaction of 4 gives access to the iron(−I) ferrato‐stannylene, 8 , giving evidence for the transient formation of such a species in the reduction of 3 . The covalently bound tin(II)‐iron(−I) compound 8 has been characterised through EPR spectroscopy, SQUID magnetometry, and supporting computational analysis, which strongly indicate a high localization of electron spin density at Fe −I in this unique d 9 ‐iron complex.