Registration Dossier

Administrative data

Endpoint:
melting point/freezing point
Type of information:
experimental study
Adequacy of study:
key study
Study period:
01 December 2010 – 21 January 2011
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: This study has been performed according to OECD and EC guidelines and according to GLP principles.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2011
Report Date:
2011

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 102 (Melting point / Melting Range)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.1 (Melting / Freezing Temperature)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
other: differential scanning calorimetry

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): SX-1
- Molecular formula: C31H24N4O4
- Molecular weight: 516.55
- Substance type: Pale yellow powder
- Physical state: solid
- Analytical purity: 99.7%
- Lot/batch No.: 008809
- Expiration date of the lot/batch: 02 November 2012
- Stability under test conditions: Stable
- Storage condition of test material: At room temperature in the dark

Results and discussion

Melting / freezing point
Melting / freezing pt.:
231 °C
Atm. press.:
1 013.25 hPa
Decomposition:
yes
Decomp. temp.:
> 350 °C
Remarks on result:
other: > 350°C: reaction or decompostition of the test substance

Any other information on results incl. tables

Preliminary test

From 400°C upwards the weight of the sample decreased significantly. At 424°C the sample weight had decreased by 25%. After the experiment, black residue was observed on the lid of the container and a black molten residue remained in the sample container (original colour: pale yellow). The change of the colour indicated reaction and/or decomposition of the test substance.

Main study

An endothermic peak between 225°C and 250°C was observed. The extrapolated onset temperature of the peak was 231.18°C. The effect was most likely obtained due to melting of the test substance.

 

At approximately 350°C, the baseline of the curve increased with the temperature. The effect was probably obtained due to reaction and/or decomposition of the test substance. After the experiment, a black molten residue remained in the sample container. The change of the colour indicated reaction and/or decomposition of the test substance during the experiment.

 

To investigate the melting peak of the test substance a repeated heating cycle was applied in the second experiment. During the first heating the extrapolated onset temperature of the melting peak was 231.18°C. During cooling a small glass transition was observed between 75°C and 25°C.

 

During the second heating a small glass transition was found between 50°C and 75°C followed by an exothermic effect between 100°C and 150°C.The latter was probably obtained due to crystallization of the test substance.The melting peak of the compound with the second heating was shifted to a lower value of 217.65°C. The reason for it was most likely that the crystalline structure of the substance was different compared to the original substance. Although of this, the results demonstrated sufficiently that the endothermic effect at 231°C with the original substance was due to melting of the test substance. After the experiment, a black molten residue remained in the sample container. It demonstrated that the test substance reacts and/or decomposes at temperatures of > 350°C.

Applicant's summary and conclusion

Conclusions:
Using DSC, the melting temperature of SX-1 was determined to be 231°C (504K).