2-[[3-acetamido-4-[(2-chloro-4-nitrophenyl)azo]phenyl](2-cyanoethyl)amino]ethyl acetate

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:

From March 29th to May 6th, 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

1995

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

2008

GLP compliance:

no

Type of method:

other: Differential scanning calorimetry and capillary method

Atm. press.:

1 017.4 hPa

Decomposition:

yes

Remarks:

at atmospheric pressure

Decomp. temp.:

ca. 120 °C

-Melting point (DSC)

The test item showed an endothermic effect in the temperature range of approx. 120 -170°C, followed by a broad exothermic effect in the temperature range of approx. 210 -410°C, with a mean energy release of -790 J/g.

Results of the DSC-measurements

No.	Sample weight [mg]	Onset of Effect [°C]	Range of effect [°C]	Weight loss [mg]	Atmospheric pressure [hPa]
PN17539	9.25	152.82	120 – 170 (endo)	4.42	1017.4
		---	220 – 380 (exo)
PN17540	11.5	154.31	120 – 170 (endo)	5.39	1017.4
		---	210 – 410 (exo)

-Measurements by the capillary method

To verify the results of the DSC measurements, three additional measurement with the capillary method were performed in the temperature range of 30 °C to 350 °C with a heating rate of 10 K/min. Starting at a temperature of approx. 130 °C the test item's colour turned darker indicating the start of a decomposition process. At approx. 150 °C the test item liquified and turned black. At approx. 150 °C the black test item crept up the walls of the capillary. The measurements were terminated at 350 °C.

Combining the results of the DSC-measurements and the capillary method, no melting of the test item could be observed, the melting point can not be separated from a decomposition reaction under air that starts before the exothermic effect is detected in the DSC. The test item started to decompose at approx. 120 °C.

Conclusions:

The test item has no melting point up to the decomposition temperature of approx. 120°C at atmospheric pressure (1017.4 hPa) as determined by differential scanning calorimetry and capillary method according to OECD guideline 102 (1995). The decomposition is accompanied by liquification of the test item.

Executive summary:

The test item was weighed into the aluminium crucible under air. Two test with about 9 -12 mg of the test item were performed. After weighing, the perforated lid was attached using a crucible press. As reference crucible, an empty aluminium crucible was used. The determination of the melting point of the test item was performed via DSC. The prepared crucibles (crucible with test item and reference crucible) were placed in the DSC apparatus. At ambient conditions, the test item is a solid. Therefore the crucibles were heated up from room temperature to 500°C at a constant heating rate of 10 K/min under air.

The melting behavior of the test item was verified by measurements with the capillary method. A small quantity of the test item was filled up to 4 -5 mm into a capillary and compacted by tapping on the capillary. The capillary and a thermometer were heated in the BÜCHI melting point apparatus from 30°C to 350°C with a heating rate of 10 K/min. the test item was observed while being heated. When the test item started to melt, the actual temperature was recorded.

The test item showed an endothermic effect in the temperature range of approx. 120 -170°C, followed by a broad exothermic effect in the temperature range of approx. 210 -410°C, with a mean energy release of -790 J/g.

To verify the results of the DSC measurements, three additional measurement with the capillary method were performed in the temperature range of 30 °C to 350 °C with a heating rate of 10 K/min. Starting at a temperature of approx. 130 °C the test item's colour turned darker indicating the start of a decomposition process. At approx. 150 °C the test item liquified and turned black. At approx. 150 °C the black test item crept up the walls of the capillary. The measurements were terminated at 350 °C.

Combining the results of the DSC-measurements and the capillary method, no melting of the test item could be observed, the melting point can not be separated from a decomposition reaction under air that starts before the exothermic effect is detected in the DSC. The test item started to decompose at approx. 120 °C.

Description of key information

The test item has no melting point up to the decomposition temperature of approx. 120 °C at atmospheric pressure (1017.4 hPa) as determined by differential scanning calorimetry and capillary method. The decomposition is accompanied by liquification of the test item.

The result about the melting point confirms the result obtained in the test regarding the thermal stability.

Additional information

OECD guideline 102 (1995).

The test item was weighed into the aluminium crucible under air. Two test with about 9 -12 mg of the test item were performed. After weighing, the perforated lid was attached using a crucible press. As reference crucible, an empty aluminium crucible was used. The determination of the melting point of the test item was performed via DSC. The prepared crucibles (crucible with test item and reference crucible) were placed in the DSC apparatus. At ambient conditions, the test item is a solid. Therefore the crucibles were heated from room temperature up to 500 °C at a constant heating rate of 10 K/min under air.

The melting behavior of the test item was verified by measurements with the capillary method. A small quantity of the test item was filled up to 4 -5 mm into a capillary and compacted by tapping on the capillary. The capillary and a thermometer were heated in the BÜCHI melting point apparatus from 30 °C to 350 °C with a heating rate of 10 K/min. The test item was observed while being heated. When the test item started to melt, the actual temperature was recorded.