A
1-l. steel bomb is charged with
200 g. (1.5 moles) of dicyclopentadiene (Note
1). The bomb is flushed with
ethylene (Note
2) and then filled while shaking to an initial pressure of 800–900 p.s.i. at 25°. Shaking is continued as the bomb is slowly heated (Note
3) to 190–200° and maintained at this temperature for 7 hours (Note
4). At the end of this period, the reaction vessel is cooled and vented, and the crude product is transferred to a simple distillation apparatus (Note
5). A fraction boiling between
93° and 100° is collected, yield
162–202 g. (
57–71%, based on
dicyclopentadiene) (Note
6). The
norbornylene may be redistilled with negligible losses to give a final product, b.p.
94–97°/740 mm., m.p.
44–44.5° (sealed capillary).