The kinetics in the sodium borohydride reduction of fluorenone and twelve 2-and 3- substituted fluorenones were determined at three temperatures in isopropyl alcohol and the entropies and enthalpies of activation calculated. A linear Hammett σ ϱ plot was obtained using meta and para σ constants. The positive ϱ value (ϱ=+ 2· 65) confirmed the nucleophilicity of sodium borohydride. Deviations of the 2-methoxy and 2- ...