Charge-Transfer Salts of Octamethylferrocenyl Thioethers and [M(mnt)2]- Complexes (M = Ni, Co, Pt). Synthesis, Structure, and Physical Properties

Article abstract of DOI:10.1021/ic9802045

The new ferrocene derivatives Fe(η⁵-C₅Me₄SR)₂ (R = Me, 4: R = t-Bu, 5) have been prepared from the corresponding cyclopentadiene and FeCl₂. 5 may be converted to the bis(thiobenzoate) 6, a protected form of dithiol 8. From 6 the octamethyl trithiaferrocenophane 9 may be obtained in good yields. Compounds 4 and 5 are easily oxidized and form paramagnetic salts containing [M(mnt)₂]^- anions (M = Co, Ni, Pt). The derivatives [Fe(η⁵-C₅Me₄SMe)₂][Ni(mnt) ₂], 14, [Fe(η⁵-C₅Me₄SMe)₂][Pt(mnt) ₂], 15, [Fe(η⁵-C₅Me₄SMe)₂][Co(mnt) ₂], 16, [Fe- (η⁵-C₅Me₄St-Bu)₂][Ni(mnt) ₂], 17, [Fe(η⁵-C₅Me₄St-Bu) ₂][Pt(mnt)₂], 18, and [Fe(η⁵-C₅Me₄St-Bu) ₂][Co(mnt)₂], 19, have been prepared and fully characterized. X-ray crystal structural studies of 14 and 16-19 have been carried out. 14 and 16 display stacks of strongly interacting [M(mnt)₂]^- anions, whereas 19 contains discrete [Co(mnt)₂] dimers. 17 and 18 are isomorphous and display a typical D⁺A^-D⁺A^- structural motif. SQUID susceptibility measurements indicate a weak ferromagnetic ordering at low temperature for these two compounds.