The kinetics of the hydrolysis of 2,2,2-trifluoro-N-(3-methyl-2-cyclohexenylidene)ethylamine (I) has been investigated in the range H0 = -1.5 to pH 13 at 25°. The reaction rate is almost independent of pH from pH 0 to pH 13, varying by a factor of less than 3. We propose a mechanism involving rate-determining attack of water on protonated I (IH+) at pH 0-7; at pH > 7 attack of hydroxide ion on IH+ is the slow step; and at H0 < 0 breakdown of the carbinolamine is rate determining. Observed solvent isotope effects (kH2O/kD2O) of 2.44 (pH ∼2) and 1.68 (pH 11-12) are consistent with this interpretation. Rates of hydrolysis for I are compared with those for a closely related β,γ-unsaturated Schiff base and found to be at least 300-fold slower at pH values near neutrality.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Organic Chemistry|
|State||Published - 1976|
ASJC Scopus subject areas
- Organic Chemistry