229012-24-2

Upstream product

• 57032-12-9 (CH₃)3SiCCHCo₂(CO)6 
• 603-35-0 triphenylphosphine 
• 1066-54-2 trimethylsilylacetylene 

Downstream Products

• 229012-23-1 Co2(CO)2(μ-CO)2(η(4)-2,5-bis(trimethylsilyl)cyclopentadienone)2 

Relevant academic research and scientific papers

Preparations and characterizations of homodinuclear complexes containing flyover bridge or cyclopentadienone ligands; X-ray crystal structures of Co2(CO)3(PPh3){μ-C(SiMe 3)=CH-CH=C(SiMe3)-CH=C(SiMe3)}, Co2(CO)2(μ-CO)2(η 4-2,5-bistrimethylsilylcyclopentadienone)2

The reaction of Co2(CO)5(PPh3)(μ-HCC-SiMe3) (1b) with 2.5 equivalent amount of trimethylsilylacetylene in refluxed THF yielded two homodinuclear complexes containing 'flyover bridge' ligands, Co2(CO)3(PPh3){μ-C(SiMe 3)=CH-CH=C(SiMe3)-CH=C(SiMe3)} (2a) and a small amount of Co2(CO)2(μ-CO)2(η 4-2,5-bistrimethylsilylcyclopentadienone)2 (4). The yield of (4) was improved, while using about five equivalent amount of trimethylsilylacetylene. The crystal structures of (2a) and (4) were determined. The structure of (2a) can be regarded as a dimetallic frame contains three linked HCCSiMe3 groups that are arranged in a 'flyover-bridge' geometry. Trimethylsilyl groups are attached to carbon atoms of the flyover bridge ligand at positions 1, 3, and 6. The ligand might be seen as the composition of two allyl groups, C1-C2-C3 and C4-C5-C6, which are joined by a single bond between C3 and C4. Each allyl group is bonded to one cobalt atom. 1,2,4-Tris-trimethysilanylbenzene was obtained from the degradation of the compound (2a). The crystal structure of (4) shows that two cyclopentadienone ligands, two terminal and two bridged carbonyls were found to be coordinated to both metal centers. The formation of the two cyclopentadienones is believed to take place via the transition metal-mediated cyclization of two alkynes with one carbon monoxide. 2,5-Bis(trimethylsilanyl)cyclopenta-2,4-dien-1-one (5) was obtained from the degradation of (4) by exposing to air in solution. The formation of (5) is believed to take place via the Diels-Alder type cyclization of two released cyclopentadienone ligands from (4).

Diphenyl-2-pyridylphosphine as a bidentate ligand in the coordination of dicobalt octacarbonyl; X-ray crystal structures of Co2(CO)4(μ-P,N-PPh2py){μ-HCCSiMe 3}, and Co4(CO)10(μ-P,N-PPh2py)

Under mild conditions, the reaction of Co2(CO)8 with HCCSiMe3 in the presence of PPh2py gave a binuclear cobalt carbonyl complex, Co2(CO)4(η2-μ2-HCCSiMe 3)(μ-PPh2py) (1a), which has both zero-valent cobalt centers coordinated by a bidentate ligand, PPh2py. PPh2py is also an effective ligand in promoting the yield of 2,5-bis(trimethylsilanyl)cyclopenta-2,4-dien-1-one. A cobalt cluster complex, Co4(CO)10(μ-P,N-PPh2py) (9) was obtained when two equivalents of Co2(CO)8 were reacted with PPh2py at a higher temperature. The phosphorus and nitrogen atoms of the ligand coordinate to cobalt in the basal and apical positions, respectively. These two compounds, 1a and 9 were characterized by spectroscopic means as well as X-ray crystal structure determination.

Diastereoselective synthesis of chiral clusters from the reaction of chiral (propargyl alcohol)Co2(CO)6 with triphenylphosphine

Dicobalt hexacarbonyl complexes of chiral (racemic) propargylic alcohols 1 react with PPh3 to form the diastereomeric complexes [R1C≡CCH(OH)R2]Co2-(CO) 5PPh3 (2) with diastereomeric excesse