Ethyltriphenylphosphonium acetate

Vapour pressure

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

vapour pressure

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 adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
EPISUITE v4.11

2. MODEL (incl. version number)
MPBPWIN v1.43 (September 2010)

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
Smiles code: P(CC(=O)(O))(c2ccccc2)(c3ccccc3)(c1ccccc1)CC
CAS: 35835-94-0

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
For detailed information about the used model please refer to the attached justification.

5. APPLICABILITY DOMAIN
For detailed information about the used model please refer to the attached justification.

6. ADEQUACY OF THE RESULT
For detailed information about the used model please refer to the attached justification.

Qualifier:

no guideline followed

Principles of method if other than guideline:

Software tool(s) used including version: The Estimation Programs Interface (EPI) SuiteTM v4.1 - Model(s) used: MPBPWIN v1.43 (September 2010)
- Model description: see field 'Attached justification'
- Justification of QSAR prediction: see field 'Attached justification'

GLP compliance:

no

Type of method:

other: QSAR prediction MPBPWIN Program, Version 1.43, Syracuse Research Cor-poration

Key result

Temp.:

25 °C

Vapour pressure:

0 Pa

Remarks on result:

other: QSAR modified Grain method

Boiling Point: 489.79 deg C (Adapted Stein and Brown Method)

 

Melting Point: 285.29 deg C (Adapted Joback Method)

Melting Point: 172.33 deg C (Gold and Ogle Method)

Mean Melt Pt : 228.81 deg C (Joback; Gold,Ogle Methods)

 Selected MP: 194.92 deg C (Weighted Value)

 

Vapor Pressure Estimations (25 deg C):

 (Using BP: 489.79 deg C (estimated))

 (Using MP: 194.92 deg C (estimated))

   VP: 1.72E-011 mm Hg (Antoine Method)

     : 2.29E-009 Pa (Antoine Method)

   VP: 8.12E-010 mm Hg (Modified Grain Method)

     : 1.08E-007 Pa (Modified Grain Method)

   VP: 2.2E-009 mm Hg (Mackay Method)

     : 2.93E-007 Pa (Mackay Method)

 Selected VP: 8.12E-010 mm Hg (Modified Grain Method)

            : 1.08E-007 Pa (Modified Grain Method)

 Subcooled liquid VP: 4.97E-008 mm Hg (25 deg C, Mod-Grain method)

                    : 6.62E-006 Pa (25 deg C, Mod-Grain method)

 

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

 TYPE  | NUM | BOIL DESCRIPTION | COEFF| VALUE 

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

 Group | 1 | -CH3             |  21.98 |  21.98

 Group | 2 | -CH2-            |  24.22 |  48.44

 Group | 1 | -COOH (acid)     | 169.83 | 169.83

 Group | 1 | >P-              |  43.75 |  43.75

 Group | 15| CH (aromatic)    |  28.53 | 427.95

 Group | 3 | -C (aromatic)    |  30.76 |  92.28

  *   |   | Equation Constant|        | 198.18

=============+====================+==========+=========

RESULT-uncorr| BOILING POINT in deg Kelvin | 1002.41

RESULT- corr | BOILING POINT in deg Kelvin | 762.95

             | BOILING POINT in deg C      | 489.79

-------------------------------------------------------

 

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

 TYPE | NUM | MELT DESCRIPTION | COEFF  | VALUE 

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

 Group | 1 | -CH3             |  -5.10 |  -5.10

 Group | 2 | -CH2-            |  11.27 |  22.54

 Group | 1 | -COOH (acid)     | 155.50 | 155.50

 Group | 1 | >P-              |  30.00 |  30.00

 Group | 15| CH (aromatic)    |   8.13 | 121.95

 Group | 3 | -C (aromatic)    |  37.02 | 111.06

  *   |   | Equation Constant|        | 122.50

=============+====================+==========+=========

  RESULT   | MELTING POINT in deg Kelvin | 558.45

           | MELTING POINT in deg C      | 285.29

-------------------------------------------------------

Conclusions:

The present QSAR prediction was conducted with the EPISuite TM; MPBPWIN v1.43 software. The software uses three separate methods for vapour pressure prediction. However, the molecular weight is the main dose descriptor. The moelcular weight of Ethyltriphenylphosphonium acetate lies within the range of molecular weights obtained from the training sets. Thus, the prediction is considered to be reliable. The predicted vapour pressure of the test item is 1.08 exp-7 Pa at 25°C (modified Grain method).
As the substance is ionic, which is not considered by the model, the "real" vapour pressure is even lower.

Reference 2

Endpoint:

vapour pressure

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

The registration substance Ethyltriphenylphosphonium acetate (EtPPAAc) is manufactured as a mixture with methanol. After drying EtPPAAc, there are still relevant residues of methanol. These residues have a higher vapour pressure (VP) as EtPPAAc has (according to the QSAR estimation, the VP of EtPPAAc is very low. The QSAR estimation is documented as supporting study to this endpoint). As a consequence, the measurement of the VP of EtPPAAc is technically not feasable due to relevant residues of methanol.

Description of key information

Due to relevant residues of methanol in the dried test substance, the measurement is technically not feasible. The vapour pressure of the methanol residues will be higher than the very low vapour pressure of the test substance.

The vapour pressure of the test substance was estimated via QSAR and is about 10exp-7 Pa (supporting study).

This is further supported by data on a structurally related source substance: The vapour pressure of Methyltriphenylphosphonium chloride was determined according to Method A4 of Commission Directive 92/69/EEC (vapour pressure balance method). The estimated maximum value of vapour pressure was determined to be ≤ 2.2E-6 Pa at 25°C.

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

25 °C