1-(2,2,4-trimethyl-3,4-dihydroquinolin-l (2H)-yl)ethanone

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 Jul- 10 Aug 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hessisches Ministerium für Umwelt, Klimaschutz, Landwirtschaft und Verbraucherschutz, Wiesbaden, Germany

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

1-(2,2,4-trimethyl-3,4-dihydroquinolin-l (2H)-yl)ethanone

EC Number:

855-228-0

Cas Number:

4497-59-0

Molecular formula:

C14 H19 N O

IUPAC Name:

1-(2,2,4-trimethyl-3,4-dihydroquinolin-l (2H)-yl)ethanone

Results and discussion

Water solubility

Water solubility:

73 mg/L

pH:

6.1

Remarks on result:

other: solubility in distilled water. RSD: 3.8 %. measured pH of the solution, resulting from 3 experiments.

Any other information on results incl. tables

Preliminary Estimation of the Water Solubility
Visual Estimation of the Solubility in distilled water
Increasing amounts of distilled water were added stepwise to approx. 100 mg of the liquid test item.

Table: Appearance of the test mixtures

Amount of test item	Total volume (mL)	Appearance of mixture
101.7 mg	0.1	undissolved particles ^1)
	0.5	undissolved particles ^1)
	1.0	undissolved particles ^1)
	2.0	undissolved particles ^1)
	10.0	undissolved particles ^1) 2)
	100	undissolved particles ^1) 2)

1) The mixture was shaken 2) sonicated for 10 min
Increasing amounts of distilled water were added to approx. 10 mg of the liquid test item. The mixtures were shaken and sonicated for 1 h.

Table: Appearance of the test mixtures

Amount of test item	Added volume of distilled water (mL)	Appearance of mixture
11.22 mg	100	undissolved particles ^1) 2)
11.05 mg	500	undissolved particles ^1) 2)
10.10 mg	1000	undissolved particles ^1) 2)

1) the mixture was shaken 2) sonicated for 1h

Result:
Even in a total volume of 1000 mL undissolved resinous particles could still be observed. This result indicated that the solubility of the test in distilled water item was probably below 10 mg/L. Therefore, in principle, the solubility in distilled water has to be determined using the "column elution method" with regard to the main test.

Pre-test based on the Flask Method

Results of the measurements:
Measured concentration in distilled water 76.6 mg/L, measured pH 5.98

Main Test:

Solubility in distilled water at different time intervals

Experiment	A	B	C	D (Blank)
Amount of test item [mg]^1)	20.39	20.29	20.61	-
Stirring time at 30 °C [h]	24	48	72	72
pH at room temperature	6.12	6.10	6.07	6.15
Solubility in distilled water [mg/L] ^2)	73.7	76.1	70.6	-

1) Amounts are the initial weights of the test item.
2) The sample purity was taken into account

Average (experiments A to C): 73 mg/L
Average pH: 6.1 ¹⁾ 
Relative standard deviation: 3.8 %

1) measured pH of the solution, resulting from 3 experiments each