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A Woodward-Fieser set of rules for servants is listed in Table 1. A diene is either homoannular with the two double bonds contained in a ring, or heteroannular with two double bonds distributed between two rings. Using these rules, the maximum UV absorption can be predicted, for example in these two compounds:[8] For polyenes with more than 4 conjugated double bonds, the Fieser-Kuhn rules must be applied. [3] The rules base the prediction on the type of chromophores present, substituents on chromophores and changes due to the solvent. [1] [2] Examples are conjugated carbonyl compounds,[3][4] conjugated dienes,[5] and polyenes. [4] Woodward`s rules are a set of rules about how organic chemical compounds absorb ultraviolet light. They provide information about the wavelength of the maximum absorption (symbol λmax) in an ultraviolet-visible (UV) spectrum of a compound. The rules are named after Robert Burns Woodward. He was a professor at Harvard University, which was awarded the Nobel Prize in Chemistry in 1965. The rules are sometimes called Woodward-Fieser rules to honor Louis Fieser. These rules predict the maximum UV absorption of compounds. Here are two examples:[7] Woodward`s rules, named after Robert Burns Woodward and also known as Woodward–Fieser rules (for Louis Fieser), are several sets of empirically derived rules that attempt to predict the wavelength of the maximum absorption (λmax) in an ultraviolet-visible spectrum of a particular compound. The inputs used in the calculation are the type of chromophores present, auxochromes (substituents on chromophores) and solvents.

[ 1] [2] Examples are conjugated carbonyl compounds,[3] [4] [5] conjugated dienes,[3][6] and polyenes. [3] [5] In the compound on the left, the reference value is 214 nm (a heteroannular diene). This group of services has 4 alkyl substituents (labeled with 1,2,3,4) and the double bond in one ring is exocyclic to the other (addition of 5 nm for an exocyclic double bond). In the compound on the right, diene is homoannular with 4 alkyl substituents. The two double bonds in the central ring B are exocyclic with respect to the rings A and C.