Cyanide-bridged complexes with Sn(II)Mn(I), Sn(II)Mn(II), Sn(IV)Mn(I) and Sn(IV)Mn(II) oxidation states

The redox-active cyanomanganese carbonyl ligands trans- and cis-[Mn(CN)(CO) (2)(PR3)(dppm)] (R=OEt or OPh, dppm=Ph2PCH2PPh2) and trans-[Mn(CN)(CO)(dppm )(2)] react with SnCl2 to give [Cl2SnII(mu -NC)(MnLx)-L-I] [L-x= trans- and cis-(CO)(2)(PR3)(dppm), R=OEt or OPh, 1-4, and trans-(CO)(dppm)(2) 5]; com plex 5 is oxidised by [Fe(eta -C5H5)(2)][PF6] to give [Cl2SnII(mu -NC)Mn-II (CO)(dppm)(2)][PF6] 5(+)[PF6](-). X-Ray structural studies on the redox rel ated pair 5 and 5(+) are consistent with oxidation localised mainly at Mn a lthough the Sn-II-NC distance increases from 2.198(3) Angstrom in 5 to 2.30 3(9) Angstrom in 5(+). The dicarbonyl cyanomanganese ligands react with SnC l4 to give trinuclear trans-[Cl4Sn{(mu -NC)MnLx}(2)] [L-x=trans- and cis-(C O)(2)(PR3)(dppm), R=OEt or OPh, 6-9], X-ray studies on 7 showing octahedral geometry at Sn(IV). The reaction of cis-[Mn(CN)(CO)(2){P(OEt)(3)}(dppm)] w ith one equivalent each of SnCl4 and PPh3 and of trans-[Mn(CN)(CO)(dppm)(2) ] with one equivalent each of SnCl4 and [N(PPh3)(2)]Cl gives heterobinuclea r [Cl-4(Ph3P)Sn-IV(mu -NC)Mn-I(CO)(2){P(OEt)(3)}(dppm)-cis] 10 and [N(PPh3) (2)][Cl5SnIV(mu -NC)Mn-I(CO)(dppm)(2)-trans], [N(PPh3)(2)](+)(11(-)), respe ctively; the latter is oxidised with [Fe(eta -C5H5)(2)][PF6] to give [Cl5Sn IV(mu -NC)Mn-II(CO)(dppm)(2)-trans] 11, completing a series of cyanide-brid ged complexes with core oxidation states Sn(II)Mn(I), Sn(II)Mn(II), Sn(IV)M n(I) and Sn(IV)Mn(II).