α-[2-(methylamino)ethyl]benzyl alcohol

Boiling point

Administrative data

Endpoint:

boiling point

Type of information:

(Q)SAR

Adequacy of study:

key 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
EPI v.4.11 (MPBPWIN v1.43), US EPA

2. MODEL (incl. version number)
MPBPWIN v1.43 (Adaptation of the Stein and Brown (1994))

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
OC(c1ccccc1)CCNC

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
MPBPWIN estimates the normal boiling point using an adaptation of the Stein and Brown (1994) method which is an extension and refinement of the Joback method (Joback, 1982; Reid et al, 1987).
The Stein and Brown (1994) method is a group contribution QSAR (quantitative structure activity relationship) method that calculates boiling point (Tb) of a compound by adding group increment values according to the relationship:
Tb = 198.2 + Σ( ni * gi )
where gi is a group increment value and ni is the number of times the group occurs in the compound.
The resulting Tb (deg K) is then corrected by one of the following equations:
Tb (corr) = Tb - 94.84 + 0.5577 Tb - 0.0007705 (Tb)^2 [Tb <= 700 K]
Tb (corr) = Tb + 282.7 - 0.5209 Tb [Tb > 700 K]
The Stein and Brown (1994) method was developed using a training dataset of boiling points for 4426 diverse organic compounds collected from the Aldrich Handbook (Aldrich, 1990).
MPBPWIN incorporates additional extensions to Stein and Brown Method such as (1) new group contributions missing from Brown and Stein (e.g. thiophosphorus [P=S], quaternary ammonium) and (2) correction factors for specific types of compounds (e.g. amino acids, various aromatic nitrogen rings, and phosphates).
Estimation Accuracy
The Stein and Brown method was derived from a training set of 4426 diverse organic compounds with following reported statistical accuracy (Stein and Brown, 1994):
Average absolute error = 15.5 deg Kelvin
Standard deviation = 24.6 deg Kelvin
Average error = 3.2%

It was then validated on a dataset of 6584 compounds collected from HODOC (1990) (compounds not used in the training set) with the following statistical accuracy (Stein and Brown, 1994):
Average absolute error = 20.4 deg Kelvin
Standard deviation = 38.1 deg Kelvin
Average error = 4.3%

The training and validation sets were not available. However, a test set of 5890 compounds with available normal boiling points was collected from the PHYSPROP Database that is included with the EPI Suite. Various compounds having boiling points were excluded (most inorganic compounds, compounds using reduced pressures).

5. APPLICABILITY DOMAIN
Currently there is no universally accepted definition of model domain. However property estimates are less accurate for compounds outside the Molecular Weight range of the training set compounds (Molecular Weight range: 16.04 – 959.17), and/or that have more instances of a given fragment than the maximum for all training set compounds.
The complete training sets for MPBPWIN's estimation methodology are not available. Therefore, describing a precise estimation domain for this methodology is not possible. The number of compounds used to derive each of the Stein and Brown descriptors is shown in Appendix F of MPBPWIN User’s Guide, but the maximum number of each descriptor that occurs in each compound is not available.
The current applicability of the MPBPWIN methodology is best described by its accuracy in predicting boiling point as described above in the Accuracy section.

6. ADEQUACY OF THE RESULT
The estimate value has been generated by a valid model. The model is applicable to α-[2-(methylamino)ethyl]benzyl alcohol with the necessary level of reliability and is sufficiently relevant for the regulatory purpose.

Data source

Reference

Reference Type:

other: QSAR

Title:

EPI Suite Version 4.11

Year:

2012

Bibliographic source:

MPBPWINv1.43 (US EPA) (2015)

Materials and methods

Principles of method if other than guideline:

- Software tool(s) used including version: MPBPWINv1.43 (US EPA)
- Model(s) used: Adapted stein & brown method
- Model description: see field 'Justification for non-standard information'
- Justification of QSAR prediction: see field 'Justification for type of information', 'Attached justification' and/or 'Cross-reference'

GLP compliance:

no

Type of method:

other: QSAR

Test material

Test material information

1

Reference substance name:

α-[2-(methylamino)ethyl]benzyl alcohol

EC Number:

255-679-8

EC Name:

α-[2-(methylamino)ethyl]benzyl alcohol

Cas Number:

42142-52-9

Molecular formula:

C10H15NO

IUPAC Name:

3-(methylamino)-1-phenylpropan-1-ol

Specific details on test material used for the study:

OC(c1ccccc1)CCNC

Results and discussion

Boiling point

Boiling pt.:

276.12 °C

Remarks on result:

other: QSAR predicted value

Applicant's summary and conclusion

Conclusions:

MPBPWINv1.43 (US EPA) predicted that the substance has a melting point = 276.12 °C.