CHAPTER TWENTY-FoUR Phenols FIGURE 24.1(a)A hy drogen bond between two phenol molecules; (b) hydr gen bonds between water and phenol molecules Intramolecular hydrogen bond H PROBLEM 24.2 One of the hydroxybenzoic acids is known by the common name salicylic acid. Its methyl ester, methyl salicylate, occurs in oil of wintergr Methyl salicylate boils over 50oC lower than either of the other two methyl hydroxybenzoates. What is the structure of methyl salicylate? Why is its boiling point so much lower than that of either of its regioisomers? 24. 4 ACIDITY OF PHENOLS The most characteristic property of phenols is their acidity. Phenols are more acidic than alcohols but less acidic than carboxylic acids. Recall that carboxylic acids have ioniza tion constants Ka of approximately 10(pKa 5), whereas the Kas of alcohols are in the 10-16 to 10-20 range(pka 16-20). The Ka for most phenols is about 10-0(pka 10 Back Forward Main MenuToc Study Guide ToC Student o MHHE WebsitePROBLEM 24.2 One of the hydroxybenzoic acids is known by the common name salicylic acid. Its methyl ester, methyl salicylate, occurs in oil of wintergreen. Methyl salicylate boils over 50°C lower than either of the other two methyl hydroxybenzoates. What is the structure of methyl salicylate? Why is its boiling point so much lower than that of either of its regioisomers? 24.4 ACIDITY OF PHENOLS The most characteristic property of phenols is their acidity. Phenols are more acidic than alcohols but less acidic than carboxylic acids. Recall that carboxylic acids have ioniza￾tion constants Ka of approximately 105 (pKa 5), whereas the Ka’s of alcohols are in the 1016 to 1020 range (pKa 16–20). The Ka for most phenols is about 1010 (pKa 10). N O O H O Intramolecular hydrogen bond in o-nitrophenol 942 CHAPTER TWENTY-FOUR Phenols (a) (b) -------------------- --------------- --------------- FIGURE 24.1 (a) A hy￾drogen bond between two phenol molecules; (b) hydro￾gen bonds between water and phenol molecules. Back Forward Main Menu TOC Study Guide TOC Student OLC MHHE Website