Jasmine Po-Kwan Lau

Synthesis, structural characterization and solution dynamics of osmium–rhodium mixed-metal cluster [Os4Rh(μ-H)4(CO)13(η2-NC5H4C2H2)]

Abstract Reaction of [Os3Rh(μ-H)3(CO)12] 1 with an excess amount of 2-vinylpyridine in refluxing CHCl3 afforded a new cluster, [Os4Rh(μ-H)4(CO)13(η2-NC5H4C2H2)] 2, in moderate yield. A pair of isomers 2a and 2b, which differ in configuration of the metallated vinylpyridine exist in the solution of 2. Through the variable temperature EXSY experiment, the activation barrier (ΔG≠) for the isomerisation of 2 was determined to be 89.8 kJ mol −1 .

Synthesis, characterization, molecular and crystal structure of osmium–rhodium mixed-metal carbide cluster,

Abstract The hexanuclear osmium–rhodium carbonyl carbide cluster [ Os 5 Rh ( μ 5 -C )( μ 3 -CO )( CO ) 13 Cp ∗ ] 3 has been synthesized in 66% yield by the ionic coupling reaction of [N(PPh3)2]2[Os5C(CO)14] 1 with [ Rh 2 ( Cp ∗ ) 2 ][ BF 4 ] 2 2. An X-ray analysis on 3 showed a square based pyramidal metal skeleton with a μ3-CO bridging a RhOs2 triangular face.

Reactivity of osmium–rhodium mixed-metal cluster [Os3Rh(μ-H)3(CO)12] towards vinyl containing ligands

Abstract Reaction of [Os 3 Rh(μ-H) 3 (CO) 12 ] ( 1 ) with an excess amount of vinylacetic acid gave two new clusters, [Os 5 Rh 2 (μ-CO)(η 6 -C 6 H 5 CH 3 )(CO) 16 ] ( 2 ) and [Os 2 Rh 2 (μ-CO) 2 (η 3 -CH 2 CHCH 2 COO) 2 (CO) 7 ] ( 3 ) in 20 and 40% yields, respectively. Treatment of [Os 3 Rh(μ-H) 3 (CO) 12 ] with vinylacetate in refluxing toluene afforded the complexes [Os 3 Rh(μ 3 -CCH 3 )(η 6 -C 6 H 5 CH 3 )(CO) 9 ] ( 4 ) and [Os 5 Rh 2 (μ-CO)(η 6 -C 6 H 5 CH 3 )(CO) 16 ] ( 2 ) in 40 and 20% yields, respectively. Thermolysis of [Os 3 Rh(μ-H) 3 (CO) 12 ] in refluxing toluene produced the known cluster compound, [Os 3 Rh(μ-H) 3 (η 6 -C 6 H 5 CH 3 )(CO) 9 ]. Treatment of 1-octene with [Os 3 Rh(μ-H) 3 (CO) 12 ] led to the isomerization to give all isomers of octenes. All the new clusters have been fully characterized by both spectroscopic and crystallographic techniques. The isomerization has been examined by GCMS technique.