Sonication effects on ester hydrolysis in alcohol–water mixtures

نویسندگان

  • Sander Piiskop
  • Hannes Hagu
  • Jaak Järv
  • Siim Salmar
  • Ants Tuulmets
چکیده

Kinetics of the neutral hydrolysis of 4-nitrophenyl chloroacetate was investigated in water and in the presence of 1 mol % of ethanol, propanol, and -butyl n alcohol without sonication and under ultrasound at 25 kHz. Similarly, the kinetics of the acid-catalysed hydrolysis of -propyl n acetate in ethanol–water binary solutions was investigated without sonication and under ultrasound at 22 kHz. The results are discussed together with corresponding data for ethyl and -butyl n acetate from previous works. It was concluded that for ester hydrolyses the solvent effects in an aqueous alcohol binary mixture are limited almost entirely to the hydrophobic ground-state stabilization by the organic co-solvent.

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تاریخ انتشار 2007