2,2,6,6-tetramethylpiperidinooxy

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-11-11 to 2010-03-08

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

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)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

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:

2,2,6,6-tetramethylpiperidinooxy

EC Number:

219-888-8

EC Name:

2,2,6,6-tetramethylpiperidinooxy

Cas Number:

2564-83-2

Molecular formula:

C9H18NO

IUPAC Name:

2,2,6,6-tetramethylpiperidin-1-ol

Test material form:

other: solid melt

Details on test material:

Product name 2,2,6,6-Tetramethylpiperidinooxy {Tempo)
CAS no. 2564-83-2
Molecular formula C9H18NO
Molecular weight 156.2 g/mol

Study design

Analytical method:

high-performance liquid chromatography

Results and discussion

Partition coefficient

Partition coefficient 1

Key result

Type:

Pow

Partition coefficient:

316

Temp.:

25 °C

pH:

> 7.3 - <= 8.5

Partition coefficient 2

Type:

log Pow

Partition coefficient:

2.5

Temp.:

25 °C

pH:

>= 7.3 - <= 8.5

Details on results:

The logPow of the test item was determined to be 2.455 and 2.457 in duplicates. Both logPow values of the test item fall within a range of ± 0.1 units, thus the test is satisfactory. The mean logPow value is 2.5.

Any other information on results incl. tables

Summary of the results of the HPLC measurements of the reference compounds and the test item:

Sample no. 1)	tR1 [min]	tR2 [min]	tR [min]	k'	logk'(x)	log Pow (y)
0	1.43	1.43	1.43 (dead time)	---	---	---
1	2.24	2.24	2.24	0.566	-0.247	0.3^2)
2	2.16	2.16	2.16	0.510	-0.292	0.5^2)
3	3.11	3.12	3.12	1.182	0.073	1.0^2)
4	4.77	4.77	4.77	2.336	0.368	1.7^2)
5	6.46	6.47	6.47	3.524	0.547	1.9^2)
6	10.81	10.82	10.82	6.566	0.817	2.6^2)
7	66.99	67.50	67.25	46.028	1.663	4.0^2)
Test item	10.68			6.469	0.811	2.455^3)
Test item		10.70		6.483	0.812	2.457^3)
Mean value						2.5

1) For the names of the reference compounds see 9.3.5.

2) Results from the OECD guideline for the testing of chemicals No. 117: ,Partition Coefficient (noctanol/ water), HPLC method" (13th April2004).

3) Interpolated from linearized function log Pow = f(log k' ) of the calibration data. Reference compounds: Urea, 2-Butanone, 4-Acetylpyridine, Acetanilide, Acetophenone, Cinnamyl alcohol, Atrazine,

The log Pow-values of the test item fall within a range of± 0.1 units, thus the test is satisfactory. Benzylbenzoate. Urea was used as dead time marker.

The linear regression of the log k, of the calibration substances against their log Pow has a correlation coefficient of r = 0.9962.

Applicant's summary and conclusion

Conclusions:

The partition coefficient n-octanol / water (Pow) of the test item was determined according to OECD guideline no. 117 [adopted on 13th April 2004] and EU test method A.8 [Council Regulation (EC) No 440/2008] with the HPLC method. The partition coefficient n-octanol / water of the test item is Pow= 316 and log Pow= 2.5.