The catalytic hydrogenation and chemical reduction of alkenes

Conversion of an alkene (or an alkyne) into an alkane is readily achieved by shaking it under hydrogen at room temperature and at atmospheric pressure in the presence of a platinium or palladium catalyst. With a Raney nickel catalyst somewhat higher temperatures and pressures are employed (see Section 2.17.1, P- 88). 

The method is illustrated by the conversion of 2-methylbut-2-ene (Expt 5.12) into 2-methylbutane (Expt 5.1). The experiment has been incorporated to illustrate the handling of low boiling point liquids, and also to illustrate some aspects of interpretative infrared spectroscopy. 

Place 100 mg of Adams platinum dioxide catalyst (Section 4.2.61, p. 459) and 

(1) This technique, rather than conventional filtration, is to be preferred in this case owing to the high volatility of the hydrocarbon. For details on the disposal and recovery of the catalyst see Section 2.17.1, p. 89, Hydrogenation at atmospheric pressure (12). 

Dicyclopentadiene is chilled until a major proportion has solidified. The material is filtered and the solid is pressed on a Buchner funnel with a spatula to remove as much liquid as possible. The solid is warmed just to melt and the process is repeated. The resulting solid has m.p. 28-30 °C (lit.4 m.p. 27-28 °C). 

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