Boronic acid, (4-ethylphenyl)-

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30.10.-17.11.2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling Point)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Remarks:

and capillary method

Key result

Boiling pt.:

>= 507 - <= 511 °C

Atm. press.:

1 013 hPa

DSC measurement

Three measurements in aluminium crucibles with a hole showed an a small endothermic effect in the temperature range 50-75 °C, a second one (melting) in the temperature range 110- 165 °C, a small exothermic effect in the temperature range 180 - 250 °C and a further endothermic effect in the temperature range of 430 - 570 °C with an onset temperature of 507 - 511 °C. The mass loss over the measurements amount to 92 wt.%.

Table 1:Boiling point (DSC measurement)

Ident.-No.	Onset / °C	Temperature range / °C	Crucible
24827	507.30	430 - 570	Aluminium with a hole
24830	511.04	430 - 570	Aluminium with a hole
24831	508.19	430 - 570	Aluminium with a hole

For the correction of the boiling point to standard atmospheric pressure (1013.3 hPa) the equation, table and graphs of H.B. Hass and R.F. Newton in „CRC Handbook of Chemistry and Physics, 74^th ed. 1993-1994", pages 15-16 and 15-17 were used.

Capillary tube in a metal block

An additional measurement with the capillary method was performed to clarify the results of the DSC measurements.

Table 2: results of the capillary method

 

No.	Set point / °C		Heating rate	End point / °C	Boiling point	Remarks
1 1	40 250	5 K/min 20 K/min		250 410		146 °C: started melting
						158 °C: melted, test item clear, yellowish
						410 °C test item light yellow

According to the capillary method no effect was observed in the temperature range 180 - 250 °C. Due to this the boiling of the test item in the temperature range 507 - 511 °C will be given as final result.

Conclusions:

The boiling range of the test item at atmospheric pressure (1013.3 hPa) is 507 - 511 °C.

Executive summary:

A study was conducted according to OECD TG 103 and Regulation (EC) No 92/69/EEC method A.2 to determine the boiling point of the test item using differential scanning calorimetry. Aluminium crucibles with a small hole were used as containers for the test item and as empty reference crucible. The test item was heated up from ambient to the final temperature (600°C) at a constant heating rate (10 K/min) in a defined atmosphere (nitrogen). A supplementary test using the capillary method was performed with the test item. In this method the test item was filled in a capillary which was then inserted in a metal block. Then the block was heated to the set point (start temperature) of the measurement and further to the maximum temperature of the device (410 °C) with a heating rate of 10 K/min.

In the DSC measurement the test item showed a small endothermic effect in the temperature range 50 - 75 °C, a second one (melting) in the temperature range 110 - 165 °C, a small exothermic effect in the temperature range 180 - 250 °C and a further endothermic effect in the temperature range of 430 - 570 °C with an onset temperature of 507 - 511 °C. The mass loss over the measurements amounts to 92 wt.%. According to the capillary method no effect was observed in the temperature range 180 - 250 °C. Thus the boiling range of the test item at atmospheric pressure (1013.3 hPa) is 507 - 511 °C.

Description of key information

The boiling range of the test item at atmospheric pressure (1013.3 hPa) is 507 - 511 °C (reference 4.3-1).

Additional information

A study was conducted according to OECD TG 103 and Regulation (EC) No 92/69/EEC method A.2 to determine the boiling point of the test item using differential scanning calorimetry. Aluminium crucibles with a small hole were used as containers for the test item and as empty reference crucible. The test item was heated up from ambient to the final temperature (600°C) at a constant heating rate (10 K/min) in a defined atmosphere (nitrogen). A supplementary test using the capillary method was performed with the test item. In this method the test item was filled in a capillary which was then inserted in a metal block. Then the block was heated to the set point (start temperature) of the measurement and further to the maximum temperature of the device (410 °C) with a heating rate of 10 K/min.

In the DSC measurement the test item showed a small endothermic effect in the temperature range 50 - 75 °C, a second one (melting) in the temperature range 110 - 165 °C, a small exothermic effect in the temperature range 180 - 250 °C and a further endothermic effect in the temperature range of 430 - 570 °C with an onset temperature of 507 - 511 °C. The mass loss over the measurements amounts to 92 wt.%. According to the capillary method no effect was observed in the temperature range 180 - 250 °C. Thus the boiling range of the test item at atmospheric pressure (1013.3 hPa) is 507 - 511 °C (reference 4.3-1).