Registration Dossier
Registration Dossier
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EC number: 204-884-0 | CAS number: 128-39-2
Dissociation constant
Administrative data
Link to relevant study record(s)
- Endpoint:
- dissociation constant
- Type of information:
- (Q)SAR
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- accepted calculation method
- Justification for type of information:
- QSAR prediction: migrated from IUCLID 5.6
- Principles of method if other than guideline:
- The acronym for the (Q)SAR SPARC stands for:-
SPARC
Performs
Automated
Reasoning in
Chemistry
The (Q)SAR was developed at the University of Georgia through grants from USEPA.
The senior developers were:
S.W. Karickhoff (USEPA retired)
L.A. Carreira (Professor University of Georgia)
S.H. Hilal (USEPA)
Several endpoints are assessed within SPARC. For the determination of pKa the major reference was:-
Hilal, Said, S. W. Karickhoff and L. A. Carreira, "A Rigorous Test for SPARC's Chemical Reactivity Models: Estimation of More Than 4300 Ionization pKa's," Quant. Struc. Act. Rel., 14, 348 1995.
Overall modeling approach is outlined in more detail in:
Carreira, L. A., S. Hilal and S. W. Karickhoff, "Estimation of Chemical Reactivity Parameters and Physical Properties of Organic Molecules Using SPARC," (Book Chapter) Theoretical and Computational Chemistry, Quantitative Treatment of Solute/Solvent Interactions, Eds. P. Politzer and J. S. Murray, Elsevier Publishers, 1994. - Dissociating properties:
- yes
- No.:
- #1
- pKa:
- 11.91
- Remarks on result:
- other: Result based on Q(S)AR
- Conclusions:
- Using SPARC Version 4.5 online calculator (Listed in Table R7.1-3 of REACH Guidance document R7) the dissociation constant for 2,6-DTBP was determined to be pKa 11.91.
- Executive summary:
Using SPARC Version 4.5 online calculator (Listed in Table R7.1-3 of REACH Guidance document R7) the dissociation constant for 2,6-DTBP was determined to be pKa 11.91.
Reference
1) pKa: Major reference:Hilal, Said, S. W. Karickhoff and L. A. Carreira, "A Rigorous Test for SPARC's Chemical Reactivity Models: Estimation of More Than 4300 Ionization pKa's," Quant. Struc. Act. Rel., 14, 348 1995.
Reference
Mechanistic Output for the Microscopic pKa
Subs are shown as SubType:[SubAnchorAtom]
| Effect / Sub | methyl:[C12] | methyl:[C8] | whole | total |
| RESONANCE | 3.12 | 3.12 | ||
| SIGMA | 0.00 | |||
| FIELD | 0.00 | |||
| PI_INDUCTION | -0.06 | -0.06 | -0.12 | |
| HYDRATION | -0.62 | -0.62 | ||
| TOTAL_PERTURBATION | 2.38 | |||
| REFERENCE | 14.30 | |||
| CALCULATED_PKA | 11.91 |
Description of key information
Using the Q(S)AR SPARC Version 4.5 online calculator, the dissociation constant for 2,6-DTBP was determined to be pKa 11.91.
Key value for chemical safety assessment
- pKa at 20°C:
- 11.91
Additional information
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