4-Ethoxy-2,3-difluorphenylboronic acid

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

04.12.15 - 12.01.16

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

no

Type of method:

flask method

Key result

Water solubility:

145 mg/L

Conc. based on:

test mat.

Incubation duration:

168 h

Temp.:

20 °C

pH:

6.3

Preliminary visual estimation of the water solubility

In a stepwise procedure, increasing volumes of distilled water were added at room temperature to a defined amount of the test item. After each addition of an amount of water, the mixture was treated with ultrasound for 15 minutes and visually checked for any undissolved particles.

 

Table 1: Results of the preliminary visual estimation of the water solubility

Amount of test item / mg	Added volume of dist. water / ml	Total volume / ml	Appearance of mixture
96.3	0.1	0.1	not dissolved
	0.4	0.5	not dissolved
	0.5	1.0	not dissolved
	1.0	2.0	not dissolved
	8.0	10.0	not dissolved

 

Three additional preliminary tests were carried out with specified amounts of the test item and 100 ml and 500 ml distilled water, respectively. After each addition of an amount of water, the miture was stirred for at least 24 hours, and visually checked for any undissolved particles.

Table 2: Results of the preliminary visual estimation of the water solubility

Amount of test item / mg	Total volume of dist. water / ml	Appearance of mixture
12.2	100	not dissolved, little precipitate
9.8	500	dissolved
2.2	500	dissolved

The preliminary visual experiments showed that the water solubility of the test item is > 10 mg/l. According to the preliminary visual estimation in the main test the water solubility was determined by the flask method.

Flask method

In a first test series the water solubility increased with the stirring time. Therefore a second test series with extended stirring times was performed. The flask method as described. The data for the evaluation are given in Table 3. After the equilibration time precipitate was observed in the flasks of the experiments excluding in the blank experiment. The water solubility was calculated from the measured and unrounded concentration values and not from the rounded values given in Table 3.

 

Table 3: Water solubility experiments of the test item

Experiment	120 h experiment	144 h experiment	168 h experiment	Blank experiment (168 h)
Amount of test item / g	38.8	38.2	38.8	--
Amount of distilled water / ml	50	50	50	50
Stirring time at 30 °C / h	120	144	168	168
pH at 23 °C	6.3	6.3	6.3	6.1
Aliquot of the flasks / ml	0.5	0.5	0.5	0.5
1st Dilution to volume / ml	1.0	1.0	1.0	1.0
Dilution factor	2	2	2	2
Measured concentration / mg/l	72.23 / 72.47	72.00 / 72.25	73.64 / 73.11	-- / --
Mean concentration / mg/l	72.35	72.12	73.37	--
Water solubility / mg/l	144.7	144.2	146.7	--

 

The water solubility of the test item at 20 °C was determined to be 145 mg/l (+/- 1 mg/l)

 

Conclusions:

The water solubility of the test item at 20 °C was determined to be 145 mg/L.

Executive summary:

The water solubility c_s of the test item at a temperature of 20 °C was determined according to the flask method described in the European Commission Regulation (EC) No. 440/2008 and in the OECD guideline 105. The water solubility was found to be c_s = was 145 mg/L (+/- 1 mg/l).

Description of key information

The water solubility c_sof the test item at a temperature of 20 °C was determined according to the flask method described in the European Commission Regulation (EC) No. 440/2008 and in the OECD guideline 105. The water solubility was found to be c_s= was 145 mg/L (+/- 1 mg/l).

Key value for chemical safety assessment

Water solubility:

145 mg/L

at the temperature of:

20 °C