name for the parent compound of this series, 1,2-propadiene. The planes of
the p bonds of allenes are perpendicular to each other. This geometry of the
p bonds causes the groups attached to the end carbon atoms to lie in
perpendicular planes. Because of this geometry, allenes with different
substitutents on the end carbon atoms are chiral. However, allenes do not
show cis–trans isomerism.
Recommended further reading
Robinson, M. J. T. Organic Stereochemistry, Oxford University Press, Oxford, 2002.
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CH3 STEREOCHEMISTRY