4-bromo-2,2-diphenylbutyric acid

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

08 July - 28 November 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7200 (Melting Point / Melting Range)

Deviations:

no

GLP compliance:

yes

Type of method:

differential scanning calorimetry

Test material

Test material information

Constituent 1

Reference substance name:

4-bromo-2,2-diphenylbutyric acid

EC Number:

253-648-3

EC Name:

4-bromo-2,2-diphenylbutyric acid

Cas Number:

37742-98-6

Molecular formula:

C16H15BrO2

IUPAC Name:

4-bromo-2,2-diphenylbutanoic acid

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): JNJ-1580774-AAA (T000835)
- Physical state: solid powder
- Appearance: slight beige

Specific details on test material used for the study:

- Batch n°: I16BB1136
- Analytical purity: 99.3% (acid titration)
- Expiration date: 02 March 2017
- Storage condition: at room temperature

Results and discussion

Melting / freezing point

Key result

Melting / freezing pt.:

ca. 150.8 °C

Atm. press.:

1 013.25 hPa

Decomp. temp.:

ca. 150.8 °C

Remarks on result:

other: A light brown molten residue remained after the preliminary and a colourless molten residue after the main test, indicating reaction and/or decomposition.

Any other information on results incl. tables

Preliminary test

From the TGA curve it could be derived that the weight of the sample decreased significantly from 150°C. At 220°C the sample weight has decreased by 30%. After the experiment, a light brown molten residue remained in the sample container (original colour: white). The change of the colour indicated reaction and/or decomposition of the test item.

Main tests

In order to determine the melting more precisely, the DSC curve with a heating rate of 20°C/min was determined and showed an endothermic peak between 125°C and 175°C. The extrapolated onset temperature of the peak was 150.858°C. The effect was most likely obtained due to melting. After the experiment, a colourless molten residue remained. To investigate the melting peak between 125°C and 175°C, a repeated heating cycle was applied. The extrapolated onset temperature of the melting peak was 150.811°C. A colourless molten residue remained in the container after the experiment.

To investigate the melting peak a lower heating rate of 5°C/minute was applied in the Experiment 3. The extrapolated onset temperature of the melting peak was 137.301°C and the endothermic peak also started at the same temperature. The extrapolated onset temperature shifted to a lower temperature. It demonstrated that probably melting in combination with reaction and/or decomposition of the test item was the reason for the endothermic effect. After the experiment, a colourless molten residue remained in the sample container.

The melting temperature of T000835 was determined as the average melting temperature obtained from Experiment 1 and Experiment 2 and equals 150.8°C (424K).

Applicant's summary and conclusion

Conclusions:

The melting temperature (with decomposition) of JNJ-1580774-AAA (T000835) was determined at 150.8°C (424.0 K) by using DSC.