Catalysts Raney cobalt

In addition to the Raney nickel catalysts, Raney catalysts derived from iron, cobalt, and copper have been examined for their action on pyridine. At the boiling point of pyridine, degassed Raney iron gave only a very small yield of 2,2 -bipyridine but the activity of iron in this reaction is doubtful as the catalyst was subsequently found to contain 1.44% of nickel. Traces of 2,2 -bipyridine (detected spectroscopically) were formed from pyridine and a degassed, Raney cobalt catalyst but several Raney copper catalysts failed to produce detectable quantities of 2,2 -bipyridine following heating with pyridine. 

Under relatively mild conditions the Ru/C catalyst poisoned with Sn (lines 1 and 2), the Ir/C catalyst (lines 14 and 15), and the Raney-cobalt catalyst modified with CoCl2 (line 19) seem likely systems to try when initiating a search for an effective method for selectively hydrogenating the C=0 bond in an a, 3-unsaturated aldehyde. 

Finely divided cobalt is pyrophoric in air [1], Raney cobalt catalyst appears to be less hazardous than Raney nickel [2],... 

A similar early example of another fifth generation dendrimer that is formed from the reaction of 1,4-diaminobutane, acrylonitrile, a Raney cobalt catalyst and hydrogen is illustrated in Figure 17. Its systemic canonical name is ... 

Dehalogenation. With either Raney nickel or Raney cobalt catalyst it is possible to reduce aromatic trifluoromethyl groups to methyl groups. ... 

Deoxygenation 9-Dia2 fluorene. Diethyl chlmophosphite. Diethylphosphonate. 2,4-Dinitrofiuorobenzene. Hexamethylphosphorous triamide. Phenyl(trihalomethyl)mercury. Phosphorus trichloride. Tri-n-butylphosphine. Triethyl phosphite. Triphenylphosphine. DESULFinuzATiON Aluminum amalgam. Lithium-AIkylamine. Nickel (Raney). Raney cobalt catalyst. Triethyl phosphite. Triphenylphosphine. 

Raney cobalt catalyst. The catalyst is prepared by the action of sodium hydroxide on a 40 60 cobalt-aluminum alloy available from Raney Catalyst Co. The procedure is that used by Billica and Adkins for the preparation of W-7 Raney nickel. 

Neupokoev et al. prepared Raney cobalt catalyst modified with tartaric acid and found that the active catalyst can be prepared by etching the Co-Al alloy with 20.3% Co content. Hydrogenation of EAA gave product with only an ee of 4%. However, Raney cobalt catalyst (RCo) prepared from Co-Al alloy with 35.5% Co content and modified with amino acids was more active in the hydrogenation of EAA and acetylacetone. Hydrogenation with an RCo-S-Leucine catalyst resulted in EHB with an ee of 8.8%... 

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