1,3-Cyclohexanedimethanamine, N1,N3-bis(2-methylpropylidene)-

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Remarks:

Equivalent or similar to EU and OECD guidelines with adjustments due to reactivity of the substance.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Version / remarks:

13 April 2004

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)

Version / remarks:

31 May 2008

GLP compliance:

yes

Remarks:

Equivalent to GLP regulation

Radiolabelling:

no

Analytical monitoring:

yes

Buffers:

Buffer solutions at pH = 4, 7 and 9 were prepared according to OECD guideline 111, ANNEX 3.

Details on test conditions:

Light and oxygen: The hydrolysis reaction was carried out using a dark thermostat to avoid photolytic effects. Nitrogen was bubbled into the water before the preparation of the solutions in order to exclude oxygen. All glassware, water and buffer solution were sterilised. The sterile buffer solutions were prepared using reagent grade chemicals and sterile ultra-pure water. The pH of each buffer solution was checked with a calibrated pH meter.
Temperature: 25 °C

Duration:

5 min

pH:

4

Temp.:

25 °C

Initial conc. measured:

5 other: µg/mL

Duration:

5 min

pH:

7

Temp.:

25 °C

Initial conc. measured:

5 other: µg/mL

Duration:

5 min

pH:

9

Temp.:

25 °C

Initial conc. measured:

5 other: µg/mL

Number of replicates:

Recovery of 1,3-cyclohexanebis (methylamine) from different buffer solutions was tested at 50 mg/L concentration level with five replicate samples.

Positive controls:

yes

Negative controls:

yes

Statistical methods:

The chromatograms were evaluated with the help of “LaChrom” chromatogram processor software. Due to the fast decomposition of Incorez 397 in contact with water (hydrolysis), the elution of the decomposition products from the column resulted in two peaks. For the determination of the concentration of Incorez 397 in the different pH buffered media, the peak areas of both peaks (peak 1 and peak 2) have been used.

Preliminary study:

Incorez 397 decomposes fast in contact with water (hydrolysis).

Transformation products:

yes

No.:

#1

No.:

#2

Details on hydrolysis and appearance of transformation product(s):

The degradation products following hydrolysis are 1,3-cyclohexanebis (methylamine) and isobutyraldehyde.

% Recovery:

0

pH:

4

Temp.:

25 °C

Duration:

5 min

% Recovery:

0

pH:

7

Temp.:

25 °C

Duration:

5 min

% Recovery:

0

pH:

9

Temp.:

25 °C

Duration:

5 min

pH:

4

Temp.:

25 °C

DT50:

< 5 min

Type:

(pseudo-)first order (= half-life)

Key result

pH:

7

Temp.:

25 °C

DT50:

< 5 min

Type:

(pseudo-)first order (= half-life)

pH:

9

Temp.:

25 °C

DT50:

< 5 min

Type:

(pseudo-)first order (= half-life)

Details on results:

Calibration:
Calibration series were prepared from separate stock solutions and samples were analysed by HPLC with three parallel injections from each. Means of the peak areas versus the concentration of Incorez 397 showed good linearity in the 1 - 100 µg/mL concentration range (R Squared 0.9999 - 1.000). The calibration curves were constructed applying linear regression.

Investigation of the hydrolysis rate of Incorez 397:

MS spectra of Incorez 397 after 5 min hydrolysis at room temperature (25 ºC) in different buffer solutions show that the hydrolysis was independent from the pH of the aqueous medium. In all buffered media comparable results after 5 minutes hydrolyses were obtained: No signal of the unchanged test item (Incorez 397) (m/z: 251.1) could be seen and the MS spectra showed intense signals of the degradation product (1,3-Cyclohexanebis (methylamine) (m/z: 143.1 amu).

Identification of the degradation products of the hydrolysis of Incorez 397:

The recovery data show, that 1,3-Cyclohexanebis (methylamine) is quantitatively formed from Incorez 397 in different aqueous buffer solutions (pH = 4, 7, 9). The storage stability of the degradation product (1,3-Cyclohexanebis (methylamine)) of Incorez 397 was evaluated in buffer solutions at pH = 4, pH = 7 and pH = 9. The storage stability of 1,3-Cyclohexanebis (methylamine) in different buffer solutions (pH = 4, 7 and 9) at room temperature was determined to be at least 5 days.

Isobutyraldehyde, the degradation product of Incorez 397 was detected at the retention time t = 2.805 ± 0.004 minute. The comparison of the corresponding MS spectra of the peaks at t = 2.805 ± 0.004 minute with a reference spectrum of Isobutyraldehyde clearly confirm the identity of Isobutyraldehyde. The molecular ion at m/z = 72.1 and characteristic fragments ions are identical both in reference spectrum and in spectra of the samples.

Validity criteria fulfilled:

yes

Conclusions:

The hydrolysis of Incorez 397 in different aqueous buffer solutions (pH = 4, 7 and 9) at room temperature (25 °C) was investigated using LC/MS and MS/MS. Measurements revealed a very fast hydrolysis of Incorez 397 (half-life < 5 minutes). The degradation products of the hydrolysis of Incorez 397 are 1,3-cyclohexanebis (methylamine) and isobutyraldehyde.

Executive summary:

The hydrolysis of Incorez 397 and the identifiaction of the decomposition products was assessed based on the OECD guideline 111 and the EU method C.7. The hydrolysis of Incorez 397 in different aqueous buffer solutions (pH = 4, 7 and 9) at room temperature (25 °C) was investigated using LC/MS and MS/MS. After 5 minutes hydrolysis under these conditions Incorez 397 could not be detected (t1/2 < 5 minutes). It could be shown that the hydrolysis of Incorez 397 was independent from the pH of the aqueous media. The degradation products (1,3-cyclohexanebis (methylamine) and isobutyraldehyde) were successfully identified using reference spectra. Recovery data showed that 1,3-cyclohexanebis (methylamine) was quantitatively formed from Incorez 397 in different aqueous buffer solutions (pH = 4, 7, 9). The storage stability of the degradation product 1,3-cyclohexanebis (methylamine) in different buffer solutions (pH = 4, 7 and 9) at room temperature was determined to be at least 5 days.

Description of key information

The hydrolysis of Incorez 397 in different aqueous buffer solutions (pH = 4, 7 and 9) at room temperature (25 °C) was investigated using LC/MS and MS/MS. Measurements revealed a very fast hydrolysis of Incorez 397 (half-life < 5 minutes). The degradation products of the hydrolysis of Incorez 397 are 1,3-cyclohexanebis (methylamine) and isobutyraldehyde.

Key value for chemical safety assessment

Half-life for hydrolysis:

5 min

at the temperature of:

25 °C

Additional information

The hydrolysis of Incorez 397 and the identifiaction of the decomposition products was assessed based on the OECD guideline 111 and the EU method C.7. The hydrolysis of Incorez 397 in different aqueous buffer solutions (pH = 4, 7 and 9) at room temperature (25 °C) was investigated using LC/MS and MS/MS. After 5 minutes hydrolysis under these conditions Incorez 397 could not be detected (t1/2 < 5 minutes). It could be shown that the hydrolysis of Incorez 397 was independent from the pH of the aqueous media. The degradation products (1,3-cyclohexanebis (methylamine) and isobutyraldehyde) were successfully identified using reference spectra. Recovery data showed that 1,3-cyclohexanebis (methylamine) was quantitatively formed from Incorez 397 in different aqueous buffer solutions (pH = 4, 7, 9). The storage stability of the degradation product 1,3-cyclohexanebis (methylamine) in different buffer solutions (pH = 4, 7 and 9) at room temperature was determined to be at least 5 days.

Please note that the key value for chemical safety assessment (half-life for hydrolysis) was set to 5 min as a worst-case value.