2-(4-aminophenyl)-6-methylbenzothiazole-7-sulphonic acid

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

GLP compliance:

yes (incl. QA statement)

Type of method:

thermal analysis

Test material

Test material information

Constituent 1

Reference substance name:

2-(4-aminophenyl)-6-methylbenzothiazole-7-sulphonic acid

EC Number:

204-979-7

EC Name:

2-(4-aminophenyl)-6-methylbenzothiazole-7-sulphonic acid

Cas Number:

130-17-6

Molecular formula:

C14H12N2O3S2

IUPAC Name:

2-(4-aminophenyl)-6-methyl-1,3-benzothiazole-7-sulfonic acid

Results and discussion

Melting / freezing point

Melting / freezing pt.:

ca. 330 °C

Atm. press.:

ca. 1 013 hPa

Decomposition:

yes

Decomp. temp.:

ca. 330 °C

Sublimation:

no

Any other information on results incl. tables

The melting temperature of the test item Dehydrothiotoluidine monosulfonic acid was investigated according to European Commission Council Regulation (EC) No. 440/2008, Annex, Part A, A.1. and the OECD Test Guideline 102.

First the melting/freezing temperature was tried to be determined using the DSC method with aluminium crucibles. This approach lead to leakages of the crucible, in one test the test item was even oozed out of the crucible.

Therefore prior to further DSC tests a visual determination using the capillary method with a melting temperature device with a metal block was performed. This visual showed a change in the colour of the test item at a temperature of 320°C coming along with the start of the melting process. With further heating to 329°C the test item was swelling to form a black foamy residue.

Finally further DSC tests with glass crucibles were performed. These tests resulted in an onset of the melting/decomposition process at a mean temperature of 330°C. Anyhow the ongoing DSC curves showed the decomposition of the test item.

The test item Dehydrothiotoluidine monosulfonic acid showed a beginning melting process accompanied with a decomposition starting at an onset of 330°C (603K)