Registration Dossier

Administrative data

Endpoint:
melting point/freezing point
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2014
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: In accordance with OECD and EU protocol and GLP methods..

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2014
Report Date:
2014

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method A.1 (Melting / Freezing Temperature)
Qualifier:
according to
Guideline:
OECD Guideline 102 (Melting point / Melting Range)
GLP compliance:
yes (incl. certificate)
Type of method:
thermal analysis
Remarks:
Metal Block Method also uses

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): Boronic Acid
-Chemical Name: 6-hydroxy-2-naphthaleneboronic acid
- Substance type: off white powder
- Storage condition of test material: room temperatire in the dark (08 to 14 October 2013), Approximately 4°C in the dark (onwards)

Results and discussion

Melting / freezing point
Melting / freezing pt.:
ca. 217 °C
Decomposition:
yes
Decomp. temp.:
ca. 217 °C

Any other information on results incl. tables

Thermal Analysis:

Thermograms and thermographic data for determinations 1 and 2 are shown in attachment 'Thermogram and Thermographic Data' below. The test item was determined to decompose while melting from approximately 217°C (490K).

Metal Block Method:

Observation times temperatures and test item appearances are shown in attachment 'Metal Block Method Results'. The test item was determined to decompose while melting from approximately 227°C(500K).

Applicant's summary and conclusion

Conclusions:
As a result of the low rate of enthalpy change during decomposition/melting, the onset temperature could only be approximated during thermal analysis.
The thermal analysis onset temperature has been reported as the definitive result as it represents the worst case scenario with respect to thermal stability. Also, the procedure utilized a standardized heating rate of 1 °C/min, compatible with the guidelines.

Visual assessment of the test item during the metal block evaluation confirmed that the thermal analysis endotherm at approximately 156 °C did not originate from a phase transition, but was attributed to the loss of a volatile component/impurity.

The test item, Boronic Acid was determined to decompose while melting from approximately 217°C (490 K).