Enantiomer-differentiating hydrogen transfer from fenchol to menthone over molten indium catalyst

Abstract

The initial rate (r₀) of the hydrogen-transfer reaction from D-fenchol to menthone has been found to obey the following equation r_0,j=k_jp_A

where k is the rate constant, p _A is the partial pressure of D-fenchol, and the subscript j denotes any one of the optical isomers (L-,D- and D,L-) of menthone. The reaction is enantiomer-differentiating: k _L > k _D , and the optical resolution of D,L-menthone takes place in the reaction between D-fenchol and D,L-menthone.

The experimental results are explained on the bases of an Eley–Rideal-type mechanism and stereochemically consistent transition-state models. Probable adsorption models for menthone are also proposed.