Woodward Fieser Rules can be applied to enones and benzophenones as well, for calculating their wavelength of maximum absorption.
Enones
a,b-unsaturated ketones form a conjugated system between a C=C and C=O. Conjugation increases the wavelength of absorption.
Presence of alkyl groups or ring residues at alpha or beta positions may help in increasing the wavelength of absorption, most probably through hyperconjugation.
Benzophenones
Ketones attached to benzene rings also form conjugated system. Substituents at o, m, and p positions may cause bathochromic shift.
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