Formation of [Os₃(CO)₁₀(EPh₃)₂(μ-Br)]⁺ (E = P, As) by Bromination: First Direct Evidence for the Bromonium Mechanism in Cluster Chemistry

Abstract

Bromination of the substituted triosmium clusters Os3(CO)10(EPh3)2 (E = P, As) yielded the cluster cations [Os3(CO)10(EPh3)2(μ-Br)]+, which crystallized as the [Os(CO)3Br3]- salts. The osmate anions were the result of nucleophilic attack of Br- on the cluster cations.

Reaction of Ru3(CO)12 with but-2-yn-1,4-diol in CH3OH/KOH solution. Crystal structure of (μ-Cl)Ru3(CO)9[μ3-η4-H2CCC(H)CH2]

“…Triruthenium clusters containing l-Cl bridges on open or closed Ru-Ru edges are known: most of them contain also other bridging ligands such as chlorine [6], sulphur [7], hydrogen [8], oxygen [9], phosphines [10] or phosphido groups [11], l-OH [12] and l-AuL [13]. In addition a number of homo- [14] and hetero-nuclear [15] tetrametallic complexes are known.…”

“…In particular BUD reacts with H 2 Os 3 (CO) 10 ; the ligand coordinates first in parallel way to give Os 3 (CO) 9 (l-CO)(HOCH 2 C 2 CH 2 OH) then undergoes loss of CO and of water to form the hydridic allenyl (l-H)Os 3 (CO) 9 [(CHO)C@C@CH 2 ] and allyl (l-H)Os 3 (CO) 9 [(CHO)CC(H)C(H)] derivatives [31]. As further discussed below, Ru 3 (CO) 12 behaves in the same way.…”