2,2'-dimethyl-2,2'-azodipropiononitrile

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Data source

Reference

Reference 1

Reference Type:

other: EPIWIN calculation

Title:

Unnamed

Year:

2018

Report date:

2018

Reference 2

Reference Type:

other: Estimation software

Title:

Estimation Programs Interface Suite for Microsoft Windows, v4.11

Author:

US-EPA

Year:

2012

Bibliographic source:

United States Environmental Protection Agency, Washington, DC, USA

Materials and methods

Test guideline

Qualifier:

no guideline required

Principles of method if other than guideline:

Estimation of log Kow using KOWWIN v1.68

GLP compliance:

no

Type of method:

other: estimation method

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

2,2'-dimethyl-2,2'-azodipropiononitrile

EC Number:

201-132-3

EC Name:

2,2'-dimethyl-2,2'-azodipropiononitrile

Cas Number:

78-67-1

Molecular formula:

C8H12N4

IUPAC Name:

2,2'-dimethyl-2,2'-azodipropiononitrile

Test material form:

solid: particulate/powder

Results and discussion

Partition coefficient

Type:

log Pow

Partition coefficient:

2.87

Temp.:

25 °C

Remarks on result:

other: The substance is within the applicability domain of the model.

Any other information on results incl. tables

-------+------+--------------------------------------------------+----------+--------

TYPE | NUM | LOGKOW FRAGMENT DESCRIPTION | COEFF | VALUE

-------+------+--------------------------------------------------+----------+--------

Frag | 4 | -CH3 [aliphatic carbon] | 0.5473 | 2.1892

Frag | 2 | C [aliphatic carbon - No H, not tert] | 0.9723 | 1.9446

Frag | 2 | -C#N [cyano, aliphatic attach] |-0.9218 | -1.8436

Frag | 1 | -N=N- [Azo] | 0.3541 | 0.3541

Const| | Equation Constant | | 0.2290

-------+------+--------------------------------------------------+----------+--------

Log Kow = 2.8733

Applicant's summary and conclusion

Executive summary:

QPRF: KOWWIN v1.68 (01 Nov. 2013)

 

1.	Substance	See “Test material identity”
2.	General information
2.1	Date of QPRF	See “Data Source (Reference)”
2.2	QPRF author and contact details	See “Data Source (Reference)”
3.	Prediction
3.1	Endpoint (OECD Principle 1)	Endpoint	Octanol-water partition coefficient (log Kow)
		Dependent variable	Octanol-water partition coefficient (log Kow)
3.2	Algorithm (OECD Principle 2)	Model or submodel name	KOWWIN
		Model version	v. 1.68
		Reference to QMRF	QMRF: Estimation of Octanol-Water Partition Coefficient using KOWWIN v1.68 (EPI Suite v4.11)
		Predicted value (model result)	See “Results and discussion”
		Input for prediction	Chemical structure via CAS number or SMILES
		Descriptor values	- Chemical structure - Fragments - Correction factors
3.3	Applicability domain (OECD principle 3)	Domains:
		1) Molecular weight (range of test data set: 18.02 to 719.92 g/mol; On-Line KOWWIN User’s Guide, Ch. 6.2.3 Estimation Domain)	Substance within range (164.21 g/mol)
		2) Fragments: Number of instances of the identified fragments does not exceed the maximum number as listed in Appendix D (On-Line KOWWIN User’s Guide)	fulfilled.
		3) Fragments: Substance has a functional group(s) or other structural features not represented in the training set, and for which no fragment coefficient was developed (Appendix D, On-Line KOWWIN User’s Guide)	Not applicable.
		4) Correction factors: Number of instances of the identified correction factor does not exceed the maximum number as listed in Appendix D (On-Line KOWWIN User’s Guide)	Not applicable as no correction factors were used.   fulfilled.
3.4	The uncertainty of the prediction (OECD principle 4)	According to REACH Guidance Document R.7a, (Nov. 2012), solubility in water is difficult to model accurately. For this reason, as well as the fact that the experimental error on solubility measurements can be quite high (generally reckoned to be about 0.5 log unit), the prediction of aqueous solubility is not as accurate as is the prediction of octanol/water partitioning.
3.5	The chemical mechanisms according to the model underpinning the predicted result (OECD principle 5)	The water solubility of a substance depends on its affinity for water as well as its affinity for its own crystal structure. In general, substances with high melting points have poor solubility in any solvent.

 

References

- US EPA (2012). On-Line KOWWIN User’s Guide.