Abstract
At room temperature the linear complex Br 2 Os 3 (CO) 12 reacts with PPh 3 and PPh 2 Me to give the substituted product Br 2 Os 3 (CO) 10 (PR 3 ) 2 (≃15%), as well as the mononuclear products Os(CO) 4 PR 3 (≃60%) and Br 2 Os(CO) 2 (PR 3 ) 2 (≃15%). The mononudear products are not formed from Br 2 Os 3 (CO) 10 (PR 3 ) 2 under the conditions of the reaction. The reaction is completely stopped by added CCl 4 or galvinoxyl, suggesting that the formations of both the trinuclear and mononuclear products are radical processes. From the reaction of Br 2 Os 3 (CO) 12 with P(OMe) 3 , the trinuclear complex Br 2 Os 3 (CO) 10 [P(OMe) 3 ] 2 is isolated in 53% yield. This complex crystallizes in the centrosymmetric triclinic space group P1 with a = 8.923 (3) Å, b = 11.657 (3) Å, c = 8.185 (3) Å, α = 98.48 (3)°, β = 111.91 (3)°, γ = 96.28 (3)°, and Z = 1; it has the structure. © 1986 American Chemical Society.