Abstract
Oxidation of Co 2+ by diphenyl diselenide in the presence of cis-[PPN][Mn(CO) 4 (SePh) 2 ], followed by carbonyl shift from Mn(I) to Co(III) and a benzeneselenolate group rearranging to bridge two metals, led directly to the thermally unstable (CO) 4 Mn(μ-SePh) 2 Co(CO)(μ-SePh) 3 Mn(CO) 3 . Dropwise addition of [PPN][SePh] to the neutral (CO) 4 Mn(μ-SePh) 2 Co(CO)(μ-SePh) 3 Mn(CO) 3 resulted in formation of a linear trinuclear complex possessing a hexaselenolatecobalt(III) core, [PPN][(CO) 3 Mn(μ-SePh) 3 Co(μ-SePh) 3 Mn(CO) 3 ]. This complex crystallized in the triclinic space group P1̄ with a = 10.878(1) Å = 15.095(2) Å, c = 25.372(4) Å, α = 95.04(1)°, β= 95.00(1)°, γ = 91.52(2)°, V = 4132(2) Å 3 , and Z = 2; final R = 0.042 and R w = 0.042. In contrast, the thermally unstable da-[PPN][Mn(CO) 4 (SeMe) 2 ], which was reacted with Co(C10 4 ) 2 ·6H 2 O and (MeSe) 2 in THF under a nitrogen atmosphere, led to the isolation of the stable heterometallic selenolate (CO) 4 Mn(μ-SeMe) 2 Co(CO)(μ-SeMe) 3 Mn(CO) 3 . Crystal data: monoclinic space group C2/c, a = 28.41.3(7) Å, b = 11.091(3) Å, c = 22.849(6) Å, β= 125.06(3)°, V = 5894(3) Å 3 , and Z = 8; final R = 0.047 and R w = 0.048. The results indicated that the distinct electronic effects between methaneselenolate and benzeneselenolate play a key role in stabilizing the neutral Mn(I)-Co(III)-Mn(I)-selenolate complexes.