The Catalytic Hydrogenolysis of Halogen Compounds¹

Abstract

Catalytic Hydrogenolysis of Halogen Compounds 261 genated to R/CH2COCH3. In no case was there reduction of the carbonyl group. However, in the previous work,2 the carbonyl groups in ArCOCHa and ArCOCH2CH2COOCH3 were almost completely reduced to methylene groups.With the primary alcohols RCH2OH, VI, and RCH2CH2OH, VII, not only was the ring smoothly dehydrogenated but the primary alcohol function was degraded by loss of one mole of hydrogen and one of carbon monoxide according to the following equations:CioH"CH3OH -> C10H8 + 3H¡ + CO CioH,iCH2CHíOH -> C10H7CH3 + 3Hi + CO

Chemoselective hydrogenation of halonitroaromatics over γ-Fe2O3-supported platinum nanoparticles: The role of the support on their catalytic activity and selectivity

“…Nevertheless, the catalytic reduction of halogen-substituted nitroaromatic compounds is often problematic because of the extensive hydrogenolysis of carbon-halogen bond which affords a mixture of haloaniline and de-halogenated aniline products [5]. De-halogenation reactions have been reported to occur also with palladium [6], platinum [7], rhodium [8], nickel [9] and copper chromite [10]. Recently, the application of new supported metals, such as Au [11,12] or Ag [13], which showed high selectivity but low catalytic activity, were proposed and developed.…”

Hydrogenation of p-chloronitrobenzene on Mo, La, Fe, and W-modified NiCoB nanoalloy catalysts

“…Raney nickel is commonly used in the hydrogenation reaction which is much cheaper. However, the hydrodehalogenation of halonitrobenzene and aromatic haloamines often occur on Raney nickel [4][5][6][7], and it suffers the disadvantage of self-igniting [8].…”

Selective Hydrogenation of Aromatic Chloronitro Compounds

“…Over usual metal catalysts, it is difficult to completely avoid the reductive dehalogenation of the haloaromatics in the hydrogenation of aromatic halonitro compounds to aromatic haloamines, because the hydrogenolysis of carbon-halogen bond is enhanced by amino substitution in the aromatic ring [1]. Dehalogenation has been shown to occur over the catalysts of platinum [1][2][3], palladium [1][2][3][4][5][6][7], rhodium [8], nickel [9] and copper chromite [10] etc.…”