Kinetis of the reaction of alkaline hydrolysis of thiophosphates in micellar and hexagonal phases of the cetyldimethylethylammonium bromide/NaOH/water system.

✍ Scribed by R.F. Bakeeva; L.A. Kudryavtseva; D.B. Kudryavtsev; V.F. Sopin

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 479 KB
• Volume: 91
• Category: Article
• ISSN: 0167-7322
• DOI: 10.1016/s0167-7322(01)00159-3

✦ Synopsis

Reactivity of 0-p-nitrophenyl-O,O-dimethylthiophosphate (A), 0-pnitrophenyl-O,Odiethylthiophosphate (I#) and 0-p-nitrophenyl-O,O-dimethylphoaphate (C) in alkaline hydrolysis in the cetyldimethylethylammonium bromide (CDAB)/NaOWwater system in micellar (MI) and and hexagonal (E) phases was investigated with the help of the spectrophotometrical method. Kinetic parameters of micellar-catalysed reactions (binding constants and rate constants in micellar pseudophase) are defined from kinetic dependence &b = f(Ccnm) in accordance with the pseudophase model. The formation of micelles results in maximum acceleration of the alkaline hydrolysis A and C by 6 and 8 times. The reaction becomes slower in an ordered E-phase in comparison with the Mi-phase for A, B and C by 16, 18 and 9 times, accordingly. The process is inhibited 3 and 5 times accordingly in comparison with aqueous alkaline hydrolysis in the E phase for A and B.