Phosphinic acid, P-[3-(acetyloxy)-3-cyanopropyl]-P-methyl-, butyl ester

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

Phosphinic acid, P-[3-(acetyloxy)-3-cyanopropyl]-P-methyl-, butyl ester

EC Number:

605-460-1

Cas Number:

167004-78-6

Molecular formula:

C11 H20 N O4 P

IUPAC Name:

Phosphinic acid, P-[3-(acetyloxy)-3-cyanopropyl]-P-methyl-, butyl ester

Test material form:

liquid: viscous

Study design

Analytical method:

high-performance liquid chromatography

Results and discussion

Partition coefficient

Partition coefficient 1

Type:

Pow

Partition coefficient:

14.8

Temp.:

22 °C

pH:

6.8

Remarks on result:

other: Temperature +/- 1°C

Partition coefficient 2

Type:

log Pow

Partition coefficient:

1.2

Temp.:

22 °C

pH:

6.8

Remarks on result:

other: Temperature +/- 1°C

Any other information on results incl. tables

Calibration
Preparation of the Reference Solutions

The preparation of the reference solutions is described in the following table:

Reference material	Purity [%]	Amount [mg]	Adjusted to x [mL]	Aliquot [mL]	Adjusted to x [mL]	Concentration [mg/L]
4-Acetylpyridine	95.9	46.50	50.0	1.25	25.0	44.6
Acetanilide	99.99	51.33	50.0	1.25	25.0	51.3
Benzonitrile	99.9	59.41	50.0	0.50	25.0	23.7
Cinnamic alcohol	98.5	58.14	50.0	1.25	25.0	57.3
Atrazine	97.4	47.63	100.0	2.50	25.0	46.4
Benzophenone	99.9	48.80	50.0	1.00	25.0	39.0
Phenyl benzoate	99.9	51.54	100.0	1.50	25.0	30.9
Thiourea (dead time)	100.1	47.12	50.0	1.25	25.0	47.2

Reference Stock Solution: The reference materials were weighed into volumetric flasks which were adjusted to the mark with acetonitrile / water (40/60, v/v).

Reference Single-Solutions: An aliquote of each reference stock solution was pipetted into separate 25 mL volumetric flasks and then filled up to mark with acetonitrile / water (40/60, v/v).

Reference Mix-Solution: An aliqoute of each reference stock solution was pipetted into one 25 mL volumetric flask and then filled up to mark with acetonitrile / water (40/60, v/v).

 

Measured Results from the Calibration Solutions
The measured retention times of the used reference materials are summarized in the following table:

Measured Results from the Calibration Solutions
The measured retention times of the used reference materials are summarized in the following table:

 

Reference material	Retention time tR [min] 1^st Injection	Retention time tR [min] 2^nd Injection	Retention time tR [min] 3^rd Injection	Retention time tR [min] Mean
4-Acetylpyridine	3.769	3.776	3.767	3.771
Acetanilide	5.132	5.156	5.148	5.145
Benzonitrile	10.767	10.882	10.878	10.842
Cinnamic alcohol	8.110	8.166	8.159	8.145
Atrazine	14.554	14.463	14.623	14.604
Benzophenone	36.763	37.234	37.251	37.083
Phenyl benzoate	60.099	60.911	60.961	60.657
Thiourea (dead time)	t0 = 2.486	t0 = 2.489	t0 = 2.480	t0 = 2.485

 

Calculation of Log K’
In the following table the measured and calculated data as well as the known POW-values of the reference materials for calibrating the measurement are summarized.
The log k’-value was calculated from the mean values as follows:

k’ = t_r - t₀ / t₀

Reference material	Mean retention time tR [min]	log k’	Theoretical log POW
4-Acetylpyridine	3.771	-0.2861	0.5
Acetanilide	5.145	0.0296	1.0
Benzonitrile	10.842	0.5267	1.6
Cinnamic alcohol	8.145	0.3575	1.9
Atrazine	14.604	0.6881	2.6
Benzophenone	37.083	1.1437	3.2
Phenyl benzoate	60.657	1.3694	3.6

 

Determination of the log P_OW of the Test Item
Preparation of the Test Item Solution
266.6 mg of the test item were weighed into a 25 mL volumetric flask and filled up to the mark with acetonitrile/water, 40/60 (v/v). With regard to the purity of the test item (90.1 %) the concentration of the resulted test solution was 9608 mg/L.

Measured Results and Determination of log K’ and log POW
To calculate the result, the equation of the calibration curve had to be transformed as follows:
Y = a * x + b >> x = (Y - b) / a
with:

a = 0.504137 a = slope of the calibration curve
b = -0.490097 b = ordinate intercept
Y = log k’ x = log POW
In the following table the measured retention time values of the test item, the calculated log k’-value and the resulting log POW values are summarized:

	1^st Inj.	2^nd Inj.	3^rd Inj.	Mean value
Retention time (test substance)	5.597	5.615	5.612	5.608
log k’	0.0977	0.1002	0.0998	0.0992
log POW	1.166	1.171	1.170	1.169
POW	14.66	14.83	14.79	14.8

 

Result:
The partition coefficient of the test item butyl (3-acetoxy-3-cyanopropyl)-methylphosphinate (AE F125869), technical substance, was at 20 °C and at neutral HPLC conditions:
P_OW = 14.8
log P_OW = 1.2
The pH value of the water used for the HPLC eluent was pH = 6.8.