Cobalt nitro

Schiff base-cobalt-nitro complexes are too mild as oxidants to react as such with alkenes. However, the addition of Lewis acids (e.g. BF3 Et20, LiPF6) to these complexes activates the nitro ligand and produces a variety of both stoichiometric and catalytic oxidations. Stoichiometric transformations involve the oxidation of sulfides to sulfoxides and 1,3-cyclohexadiene to benzene.467 Alcohols such as benzyl alcohol and cycloheptanol are catalytically transformed into the corresponding carbonyl compounds.467,474... 

A somewhat similar catalytic acetoxylation of ethylene to vinyl acetate by 02 has been carried out in acetic acid in the presence of a Pd(OAc)2-pyCo(TPP)N02 system.472 A stoichiometric epoxidation of alkenes such as 1-octene or propene by cobalt-nitro complexes has been shown to occur in the presence of thallium(III) benzoate. Oxygen labeling studies showed that the epoxide oxygen atom comes only from the nitro ligand (equation 197).473... 

Cobalt and Nitrogen—Cobalti-hexa-nitrites—Cobalti-tetra-nitrites—Cobalti-tri-nitrites—Cobalt and Phosphorus, Arsenio, and Antimony—Cobalt and Carbon—Cobalto-oyanides—Cobalti-oyanides—Cobalt Nitro-oyanides—Cobalt and Silicon—Smalt—Cobalt and Tin—Cobalt and- Boron—Detection and Estimation of Cobalt. 

The combination of the cobalt nitro complex 43 or [Co(TPP)(py)(N02)] (44, TPP = tetraphenylporphyrin) with palladium(II) complex [(PhCN)2PdCl2] indeed demonstrated catalytic activity toward oxidation of olefins to aldehydes or ketones. At 70°C in a gas flow of olefin and O2, the Co-N02/Pd(II) catalytic system (1 2) afforded the formation of acetaldehyde from ethylene in TONs up to... 

Tovrog BS, Diamond SE, Mares F (1979) Oxygen-transfer from ligands - cobalt nitro complexes as oxygenation catalysts. J Am Chem Soc 101 270-272... 

Tovrog BS, Mares F, Diamond SE (1980) Cobalt-nitro complexes as oxygen-transfer agents -oxidation of olefins. J Am Chem Soc 102 6616-6618... 

The cobalt nitro complexes [pyCo(saloph)N02] and [pyCo(TPP)N02] catalyze the O -oxidation of primary alcohols to aldehydes and that of secondary alcohols to ketones [40]. Lewis acids (A) like BF. Et O or... 

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