The excited-state proton-transfer (ESPT) reactions of 1-propyl-2-naphthol (PN), 1-(3-hydroxypropyl)-2-naphthol (HPN), and 1-(2,3-dihydroxypropyl)-2-naphthol (DPN) in aqueous methanol solutions have been investigated. The hydroxypropyl and dihydroxypropyl side chains have a pronounced effect on the rate of the proton transfer and on the number of water molecules involved, indicating that proton transfer in alcoholic solvents is more complex than simple models of water clusters can accommodate. Alternative models in which a side chain facilitates the formation of the requisite geometry for proton transfer are discussed.