A balanced linear equation of the extended Woodward UV rules for all types of α,β-unsaturated ketones

A more accurate balanced linear equation, λcal′ = 213.05 + 11.25Nsub + 5Nexo, based on the simplified linear equation, λcal = 211 + 12Nsub + 5Nexo, was developed for the Woodward UV rules for the calculation of the UV maximum absorption wavelengths (λmax) of α,β-unsaturated ketones. These linear equations revealed a remarkable logical and mathematical relationship hidden in the original descriptive Woodward UV rules, and were found to be accurate and applicable to all eight possible types of α,β-unsaturated ketones in the extended Woodward UV rules.