5-oxo-DL-proline

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

25 July 2008 to 17 November 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Boiling pt.:

541 K

Atm. press.:

100.89 kPa

Decomposition:

yes

Remarks on result:

other: Determination 1 (performed under air, static)

Boiling pt.:

536 K

Atm. press.:

100.89 kPa

Decomposition:

yes

Remarks on result:

other: Determination 2 (performed under nitrogen)

Table 1: Thermographic Data

	Thermal Event	Interpretation	Temperature
			°C	K
Determination 1 (0.0051 g)	Broad endotherm	Start of decomposition	268	541
Determination 2 (0.0051 g)	Broad endotherm	Start of decomposition	263	536

Conclusions:

Under the conditions of the study, the boiling point of the test material was determined (mean of 2 determinations) as overall decompostion temperature onset, (approximately) 536 to 541 K.

Executive summary:

The boiling point of the test material was investigated in study; conducted under GLP conditions and in accordance with the standardised guideline EU Method A.2., by differential scanning calorimetry.

As a result of the low rate of enthalpy change during decomposition, the onset temperature could only be approximated. Similar thermographic profiles were obtained using air and nitrogen atmospheres; this indicated that the observed decomposition in both determinations was probably thermal and not oxidative.

The test material has been determined to decompose from approximately 536 K at 100.89 kPa. As the test material decomposed, no value for boiling temperature could be determined.

A calculated value of boiling temperature gave a result of 612 K at 101.325 kPa.

Under the conditions of the study, the boiling point of the test material was determined (mean of 2 determinations) as overall decompostion temperature onset, (approximately) 536 to 541 K.

Description of key information

Boiling point (with decomposition) = 536 K, EU Method A.2., differential scanning calorimetry, Butler & O'Connor (2008)

A calculated value of boiling temperature gave a result of 612 K at 101.325 kPa.

Key value for chemical safety assessment

Boiling point at 101 325 Pa:

612 K

Additional information

The boiling point of the test material was investigated in study; conducted under GLP conditions and in accordance with the standardised guideline EU Method A.2., by differential scanning calorimetry. The study was assigned a reliability score of 1 in line with the principles for assessing data quality as defined by Klimisch (1997).

As a result of the low rate of enthalpy change during decomposition, the onset temperature could only be approximated. Similar thermographic profiles were obtained using air and nitrogen atmospheres; this indicated that the observed decomposition in both determinations was probably thermal and not oxidative.

The test material has been determined to decompose from approximately 536 K at 100.89 kPa. As the test material decomposed, no value for boiling temperature could be determined.

A calculated value of boiling temperature gave a result of 612 K at 101.325 kPa.

Under the conditions of the study, the boiling point of the test material was determined (mean of 2 determinations) as overall decompostion temperature onset, (approximately) 536 to 541 K.