Efficient microwave syntheses of the compounds Os3(CO)11L, L=NCMe, py, PPh3

Microwave-Assisted Synthesis of Coordination and Organometallic Compounds

“…Ligand substitution reactions of Ru 3 (CO) 12 with triphenylphosphine were also studied in real time by means of a digital camera interfaced with the microwave unit. Microwave-assisted ligand substitution reactions of Os 3 (CO) 12 in a remarkably short period of time led to the labile complex Os 3 (CO) 11 (NCMe) in high yield without the need for a decarbonylation reagent such as trimethylamine oxide (Jung et al, 2009). Additionally, MWH of Os 3 (CO) 12 in a relatively small amount of acetonitrile was shown to be a useful first step in two-step, one-pot syntheses of the cluster complexes Os 3 (CO) 11 (py) and Os 3 (CO) 11 (PPh 3 ).…”

Microwave preparation of osmium clusters with anticancer activity; rapid syntheses of Os6(CO)18, Os3(CO)10(acetonitrile)2, and Os3(μ-H)(μ-OH)(CO)10

“…These five compounds also happen to be the most important starting materials in osmium cluster chemistry [8]. The standard methods of synthesizing these clusters involve extended reaction times and copious amounts of solvents primarily due to the stability of their common starting material, Os 3 (CO) 12 [9]. Microwave heating is emerging as a versatile tool for the preparation of inorganic and organometallic complexes [10].…”

“…It usually offers several advantages over traditional methods including shorter reaction times, lower energy costs and less solvent usage. In the last few years, microwave heating has been used for the high-yield conversion of Os 3 (CO) 12 to several other osmium clusters in a fraction of the time required by conventional heating [11,12]. Leadbeater and Shoemaker reported the fast and efficient synthesis of cluster 1 in a microwave reactor [13].…”

“…Cluster 2, Os 3 (CO) 10 (NCMe) 2 , is the most common synthon for derivatives of Os 3 (CO) 12 [8]. This "activated" cluster is the starting material of choice for ligand substitution reactions since two carbonyl groups have been replaced by much more labile acetonitrile ligands.…”

“…This "activated" cluster is the starting material of choice for ligand substitution reactions since two carbonyl groups have been replaced by much more labile acetonitrile ligands. The standard method for the synthesis of this material calls for the slow addition of trimethylamine-N-oxide (Me 3 NO) to an acetonitrile solution of Os 3 (CO) 12 at 40 C under a nitrogen atmosphere [15]. A period of at least 7 h is required to complete the procedure for several reasons including the need to exclude air and moisture and the difficulty of dissolving the Os 3 (CO) 12 .…”