Search results
Results from the WOW.Com Content Network
Dicobalt octacarbonyl is an organocobalt compound with composition Co 2 (CO) 8. This metal carbonyl is used as a reagent and catalyst in organometallic chemistry and organic synthesis , and is central to much known organocobalt chemistry .
Dicobalt octacarbonyl is used commercially for hydroformylation of alkenes. A key intermediate is cobalt tetracarbonyl hydride (HCo(CO) 4). Processes involving cobalt are practiced commercially mainly for the production of C7-C14 alcohols used for the production of surfactants.
Isomers of dicobalt octacarbonyl. Apart from X-ray crystallography, important analytical techniques for the characterization of metal carbonyls are infrared spectroscopy and 13 C NMR spectroscopy. These two techniques provide structural information on two very different time scales.
Transition metal alkyne complexes are often formed by the displacement of labile ligands by the alkyne. For example, a variety of cobalt-alkyne complexes arise by the reaction of alkynes with dicobalt octacarbonyl. [2] Co 2 (CO) 8 + R 2 C 2 → (R 2 C 2)Co 2 (CO) 6 + 2 CO. Many alkyne complexes are produced by reduction of metal halides: [3]
Dicobalt octacarbonyl (Co 2 (CO) 8) is an orange-red crystal with two isomers in solution: [22] It reacts with hydrogen or sodium to form HCo(CO) 4 or NaCo(CO) 4. It is a catalyst in carbonylation and hydrosilylation reactions. [23] Cobaltocene (Co(C 5 H 5) 2) is a cyclopentadiene complex of cobalt. It has 19 valence electrons and is easily ...
It can be formed through the reaction between dicobalt octacarbonyl and iodine azide. [1] Co 2 (CO) 8 + 4IN 3 → 2Co(N 3) 2 + 8CO + 2I 2. Properties.
The addition of dicobalt octacarbonyl to the alkyne of propargylic ether (1) gives the dicobalt intermediate 2. Reaction with tetrafluoroboric acid or a Lewis acid gives the key dicobalt octacarbonyl-stabilized propargylic cation (3a and 3b). Addition of a nucleophile followed by a mild oxidation gives the substituted alkyne (5).
In the case of dicobalt octacarbonyl or Co 2 (CO) 8 as a catalyst, pentan-3-one can arise from ethene and CO, in the absence of hydrogen. A proposed intermediate is the ethylene-propionyl species [CH 3 C(O)Co(CO) 3 (ethene)] which undergoes a migratory insertion to form [CH 3 COCH 2 CH 2 Co(CO) 3 ].