Keto Tautomer Enol Tautomer %Lnol Tautomer 00 pKa=9 pure liquid water solution hexane solution 2 CH3 76 20 92 2,4-pentanedione 0 0 pK=11 0 CHa 8 04 46 H2 ethyl acetoacetate 0 K,=13 0.1 0 1 diethymae