1,1,1,3,3,3-hexafluoro-2-methoxypropane

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

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: US EPA MPBPWin v1.43

2. MODEL (incl. version number): MPBPWin v1.43

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL: COC(C(F)(F)F)C(F)(F)F

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL: MPBPWIN estimates melting point by two different methods.  The first is an adaptation of the Joback group contribution method for melting point and the second is a simple Gold and Ogle method. The original Joback methodology used a data set of 388 compounds to derive 41 chemical structure group descriptors via multiple linear regression.  The Joback adaptation in MPBPWIN is an extension of the original method to include the same groups as in the adapted Stein and Brown boiling point method.  In addition, MPBPWIN also uses melting point correction factors for specific structures. The second estimation method (Gold and Ogle), simply relates melting point to boiling point. MPBPWIN then averages the adapted Joback and the Gold and Ogle estimates and reports the average estimate as well as both individual estimates. For the substet of compounds with known boiling points and melting points, the following statistical accuracy has been reported:

- n = 10051
- r2 = 0.63
- std deviation = 63.9 deg C
  - avg deviation = 48.6 deg C

5. APPLICABILITY DOMAIN: There is no universally accepted definition of the model domain but the model is reported to be most reliable when the target substance falls within the molecular weight range of the training set and/or that have more instances of a given fragment than the maximum for all training set compounds. In that regard, the target substance, with a molecular weight of 182.07 and C, CH, CH3, O, and F fragments, falls well within the training set having a molecular weight range of 30.3 - 627.62 and a large number of compounds with like frangments.

6. ADEQUACY OF THE RESULT: The predicted Melting Point is -120.25 deg C. There is no measured value to compare against.

Principles of method if other than guideline:

QSAR estimation using EPA MPBPWin v1.43.

Specific details on test material used for the study:

SMILES : COC(C(F)(F)F)C(F)(F)F
CHEM : 1,1,1,3,3,3-Hexafluoro-2-methoxypropane
MOL FOR: C4 H4 F6 O1
MOL WT : 182.07

Key result

Melting / freezing pt.:

ca. -120.25 °C

Atm. press.:

1 atm

Melting Point: -122.71 deg C (Adapted Joback Method)

Melting Point: -117.79 deg C (Gold and Ogle Method)

Mean Melt Pt : -120.25 deg C (Joback; Gold,Ogle Methods)

Selected MP: -120.25 deg C (Mean Value)

Note: EPA MPBPWin v1.43 also estimated a vapor pressure of 39.4 kPa which is consistent with a measured vapor pressure of 36.1 kPa, thus supporting the reliability of the melting point estimate.

Conclusions:

The substance has an estimated melting point of -120.25 deg C.

Executive summary:

The melting point of the substance was estimated by QSAR using EPA MPBPWin v1.43 and determined to be -120.25 deg C.

Description of key information

The estimated melting point of the substance is -120.25 deg C.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-120.25 °C