| abstract |
A method for preparing an unsaturated compound, comprising dehydrogenation of a corresponding saturated compound in the presence of a catalytic system under conditions that result in the loss of one or more hydrogen (H2) molecules per molecule of the saturated compound, wherein the unsaturated compound is a compound of formula I (a) or I (b) and the saturated compound is a compound of formula II: ** (See formula) ** wherein R is H or = O; and Q is CH2, CH2CH2, CH (CH3) or C (CH3) 2. |