2-Butenoic acid, 4,4,4-trifluoro-3-(methylamino)-, ethyl ester, (2Z)-

Hydrolysis

Administrative data

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

ethyl (2Z)-4,4,4-trifluoro-3-(methylamino)but-2-enoate

EC Number:

801-277-8

Cas Number:

507448-65-9

Molecular formula:

C7H10F3NO2

IUPAC Name:

ethyl (2Z)-4,4,4-trifluoro-3-(methylamino)but-2-enoate

Study design

Analytical monitoring:

yes

Buffers:

Citrate buffer pH 4.0 20 mM sodium citrate
Phosphate buffer pH 7.0 20 mM sodium phosphate
Borax buffer pH 9.0 20 mM sodium tetraborate

Results and discussion

Details on results:

Results for pH 4 buffer and pH 7 buffer solutions
The half-life time of CA 2455 in the pH 4 buffer solution and in the pH7 buffer solution was estimated from the results of the preliminary test to be less than one day at 25 °C and, consequently, must also be less than one day at 20 °C. The final pH values from these experiments were determined to be 4.0 and 7.2 respectively.

Arrhenius Fit – Extrapolation to 25 °C and 20 °C for pH 0
Using the Arrhenius equation, a plot of the logarithm of kobs, determined at 50.0 °C, 40.0 °C and 30.0 °C versus the reciprocal of the temperature (in kelvin) was made.

Refer to Table 1

Substitution of 25.0 °C and 20.0 °C (as the reciprocal of the absolute temperature) in the Arrhenius equation yielded the log k values at these two temperatures.


Summary of Results

Temperature (°C) 25.0 20.0
k obs 0.005047 hours -1 0.002974 hours -1
t ½ 137 hours 233 hours
t ½ 5.72 days 9.71 days

For Graphical Presentation of the Arrhenius Extrapolation to 25 °C and 20 °C for pH9 refer to CA 2455 Figure 1.

Any other information on results incl. tables

Table 1

 

Hydrolysis Solution	Rate Constant (hours^-1)		Log rate Constant (hours^-1)	Temperature
	Individual	Average		1/K	°C
H93 H94   H95 H96   H97 H98	0.056803 0.056018   0.021692 0.021719   0.008590 0.008470	0.056411     0.021706     0.008530	-1.2486     -1.6634     -2.0691	0.003095     0.003193     0.003299	50.0     40.0     30.0

 

Applicant's summary and conclusion

Conclusions:

The rate of hydrolysis of CA 2455 has been determined at three pH values.
The half-life times (t½) of the test substance were determined either by extrapolation of the experimental values (for buffer solutions pH 9.0) or by estimation from the preliminary test (buffer solutions pH 4.0 and pH 7.0).
Half-life times (t½)
Buffer solution At 20°C At 25° C
pH 4.0 < 1 day < 1day
pH 7.2 < 1 day < 1day
pH 9.2 233 hours 137 hours

These results have been quoted to three significant figures, where appropriate.

Executive summary:

 

The rate of hydrolysis of CA 2455 has been determined at three pH values.  

The half-life times (t½) of the test substance were determined either by extrapolation of the experimental values (for buffer solutions pH 9.0) or by estimation from the preliminary test (buffer solutions pH 4.0 and pH 7.0). 

Half-life times (t½)
Buffer solution	At 20°C	At 25° C
pH 4.0	< 1 day	< 1day
pH 7.2	< 1 day	< 1day
pH 9.2	233 hours	137 hours

 

These results have been quoted to three significant figures, where appropriate.