Investigation of the reduction of aceto- and propiophenone in the presence of Co and Ni catalysts: Influence of poisons

Conclusions

• 1. In the presence of a Co catalyst at temperatures up to 120° and pressures up to 80 atm, aceto-and propiophenone are reduced only at the carbonyl group; there are no products of hydrogenation of the aromatic ring in the catalyzate.

• 2. The alkylphenylcarbinol formed undergoes hydrogenolysis at the C-OH bond on a Co catalyst even at room temperature. At 100° and 80 atm, an aliphatic-aromatic ketone is entirely reduced to the hydrocarbon.

• 3. In the presence of an Ni-Al₂O₃ catalyst, reduction of the C=O group of the ketone and hydrogenolysis of the C-OH bond of the alkylphenylcarbinol predominate, but the aromatic ring is also partially hydrogenated.

• 4. Hydrogenation and hydrogenolysis proceed on different portions of the active surface: selective reduction of the ketone to an alkylphenylcarbinol can be achieved by partial poisoning of a Co or Ni catalyst with cadmium (or lead).