1,3,3-trimethyl-2-[(methylphenylhydrazono)methyl]-3H-indolium chloride

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 15, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

GLP compliance:

no

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

211.3 °C

Decomposition:

yes

Decomp. temp.:

> 215 °C

Melting point / melting range: DSC measurement

Two DSC measurements with a heating rate of 10 K/min showed an endothermal effect (melting) in the temperature range of 205 – 215 °C, followed by an exothermal effect in the temperature range 215 – 280 °C. The onset temperature (see Table1) was derived from the intersection of the tangent line with the highest slope of the endothermal peak with the baseline. In the first measurement a mass loss of 61 % occurred and a black residue was obtained after the measurement. The second measurement was terminated shortly after the beginning of the exothermal peak. Here a mass loss of only 4 % was determined and the test item was a solidified, black melt after the measurement.

The results of the DSC measurements are summarized in Table 1.

Table1: Melting point (DSC measurements)

Ident No.	Test item / mg	Starting temperature / °C	Final test temperature / °C	Temperature range (endo-thermal) / °C	Onset (melting) / °C	Crucible	Observations after the measurement
36874	9.14	25	500	205 – 215	211.04	Aluminium with a hole	Black residue, 61 % mass loss
36876	8.55	25	220	205 – 215	211.60	Aluminium with a hole	Test item was a solidified, black melt, 4 % mass loss

Due to the different mass losses in the first and second measurement and the observation of a solidified black melt in the second measurement, the melting point was determined to 211.3 °C. The melting point is directly followed by decomposition, starting at approx. 215 °C.

Executive summary:

The test item had a mean melting point of 211.3 °C.

Description of key information

The test item had a mean melting point of 211.3 °C.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

211.3 °C