4-Butoxy-2,3-difluorophenylboronic Acid (contains varying amounts of Anhydride)

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:

12.12.2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

GLP compliance:

no

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

>= 127 - <= 130 °C

Atm. press.:

1 013 hPa

Decomposition:

yes

Decomp. temp.:

130 °C

Two DSC measurements with a heating rate of 10 K/min showed an endothermal effect (melting) in the temperature range of 90 - 150 °C. This endothermal effect was directly followed by an exothermal effect. The onset temperature was derived from the intersection of the tangent line with the highest slope of the endothermal peak with the baseline.

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

Table 1: Melting point (DSC measurements)

Ident No.	Test item/ mg	Starting temperature / °C	Final test temperature / °C	Temperature range (endothermal) / °C	Onset (melting)/ °C	Crucible	Observations after the measurement
36743	13.73	25	500	90 - 150	127.37	Aluminium with a hole	Test item was discoloured to black, Mass loss: 82 %
36744	17.84	25	150	105 - 150	129.84	Aluminium with a hole	Test item was a solidified melt, Mass loss: 13 %

The DSC measurement showed a mass loss of 13 % after the endothermal effect. Therefore it was concluded that the test item melted under decomposition in a range of 127 °C to 130 °C.

Conclusions:

The DSC measurements (25 - 150 °C) showed that the test item melted under decomposition in a range of 127 to 130 °C.

Executive summary:

A study was conducted according to OECD test guideline 102, Regulation (EC) No 440/2008 method A.1. The  melting range was determined by differential scanning calorimetry (DSC 25 - 150 °C). The test item and the reference are heated up from the starting temperature to the final temperature at a constant heating rate in a defined atmosphere (nitrogen). Open crucibles are used as containers for the test item and as empty reference crucible. The quantity of heat absorbed or released is measured and recorded. The DSC measurements (25 - 150 °C) showed that the test item melted under decomposition in the range of 127 - 130 °C. 

Description of key information

A study was conducted according to OECD test guideline 102, Regulation (EC) No 440/2008 method A.1. The  melting range was determined by differential scanning calorimetry (DSC 25 - 150 °C). The test item and the reference are heated up from the starting temperature to the final temperature at a constant heating rate in a defined atmosphere (nitrogen). Open crucibles are used as containers for the test item and as empty reference crucible. The quantity of heat absorbed or released is measured and recorded. The DSC measurements (25 - 150 °C) showed that the test item melted under decomposition in the range of 127 - 130 °C.