Page 1160 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg

and polyene photochemistry. For triplet excited states of dienes, the minimum energy 1145
corresponds to a twisted diradical that consists of an allylic radical and a localized
PROBLEMS
radical. The pattern continues for higher polyenes with the excited states consisting of
components similar to those recognized for simple alkenes and dienes.

General References

D. R. Arnold, N. C. Baird, J. R. Bolton, J. C. D. Brand, P. W. M. Jacobs, P. de Mayo, and W. R. Ware,
Photochemistry; An Introduction, Academic Press, New York, 1974.
D. O. Cowan and R. L. Drisko, Elements of Organic Photochemistry, Plenum Press, New York, 1976.
J. M. Coxon and B. Halton, Organic Photochemistry, Cambridge University Press, Cambridge, 1974.
A. Gilbert and J. Baggott, Essentials of Molecular Photochemistry, CRC Press, Boca Raton, FL, 1991.
W. Horspool and D. Armester, Organic Photochemistry: A Comprehensive Treatment, Ellis
Horwood/Prentice-Hall, Chichester, 1992.
W. H. Horspool and P.-S. Song, eds., Organic Photochemistry and Photobiology, CRC Press, Boca Raton,
FL, 1995.
W. Horspool and F. Lenci, eds., CRC Handbook of Organic Photochemistry and Photobiology, 2nd Edition,
CRC Press, Boca Raton, FL, 2004.
J. Kagan, Organic Photochemistry: Principles and Applications, Academic Press, San Diego, 1993.
M. Klessinger and J. Michl, Excited States and Photochemistry of Organic Molecules, VCH, New York,
1995.
J. Kopecky, Organic Photochemistry, VCH, New York, 1992.
P. de Mayo, ed., Rearrangements in Ground and Excited States, Vol. 3, Academic Press, New York, 1980.
J. Michl and V. Bonacic-Kouteky, Electronic Aspects of Organic Photochemistry, John Wiley, New York,
1990.
N. J. Turro, Modern Molecular Photochemistry, Benjamin-Cummings, Menlo Park, CA, 1978.
A. West, Flash and Laser Photolysis in Investigation of Rates and Mechanisms of Reactions,
C. F. Bernasconi, ed., Techniques of Chemistry, Vol. VI, Part 2, Wiley-Interscience, New York, 1986.
H. E. Zimmerman, ”Topic in Photochemistry,” Top. Curr.Chem., 100, 45 (1982).

Problems

(References for these problems will be found on page 1168.)

12.1. The bridged radical 1-A has been suggested as a possible intermediate in the
photochemical decarbonylation of 3-phenylpropanal. Suggest an experiment
to test this hypothesis.

.

H CCH 2
2
1-A
12.2. Predict the structure, including all aspects of the stereochemistry, based on
orbital symmetry principles for the following photochemical electrocyclic and
cycloaddition reactions.