2,4-dinitroanisole

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

June 2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

not specified

Type of method:

flask method

Specific details on test material used for the study:

DNAN, a light yellow powder, provided by Defense Research and Development Canada (Valcartier, QC) and used as received.

Key result

Water solubility:

ca. 0.216 g/L

Conc. based on:

test mat. (dissolved fraction)

Incubation duration:

2 wk

Temp.:

22 °C

pH:

6.7

Details on results:

The aqueous solubility of DNAN at room temperature (22ºC) was found to be 0.216 g/ L.
Boddu et al. (2008) estimated the aqueous solubility of DNAN to be 0.276 g/ L at 25ºC.

Conclusions:

Solubility of 2,4-dinitroanisole is 0.216 g/L in water at 25°C.

Executive summary:

The report summarizes findings on the environmental fate and ecological impact of DNAN. Aqueous solubility (S_w), octanol/water partition coefficients (K_ow), sorption and stability of DNAN in two soils (DRDC-08 and DRDC-09 as provided by DRDC) were measured.

Following a similar protocol than OECD Guideline 105 (Water Solubility), the study found that solubility of 2,4-dinitroanisole is 0.216 g/L in water at 25°C.

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

June 2014

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Qualifier:

no guideline followed

Principles of method if other than guideline:

Previously published method: Monteil-Rivera, F., Paquet, L., Deschamps, S., Balakrishnan, V.K., Beaulieu, C., Hawari, J., 2004. Physico-chemical measurements of CL-20 for environmental applications – comparison with RDX and HMX. J. Chromatogr. A 1025, 125–132.

GLP compliance:

not specified

Type of method:

flask method

Specific details on test material used for the study:

DNAN (98.4%) was provided by Defense Research and Development Canada (Valcartier, QC).

Key result

Water solubility:

ca. 0.213 g/L

Conc. based on:

test mat. (dissolved fraction)

Incubation duration:

ca. 2 wk

Temp.:

25 °C

pH:

5.5

Details on results:

The aqueous solubility of DNAN and its major products follows the order: DNAN < 2-ANAN < 4-ANAN < DAAN. Sequential reduction of the nitro groups into amino groups increased the water solubility of the aromatic chemical. However, while the solubility of 4-ANAN (4.43 ± 0.06 g/ L) was twenty times higher than that of DNAN (0.213 ± 0.012 g/ L), that of 2-ANAN (0.252 ± 0.008 g/ L) was only slightly higher than DNAN. Two chemical phenomenons might explain these different solubilities: 1/the para isomer might have an ability to form solute–solvent intermolecular H-bonding that the ortho isomer cannot form due to the intramolecular H-bonding, or 2/the para isomer is more easily protonable than the ortho isomer. In water, substituted aminoaromatics (ArNH2) equilibrate with their acidic protonated forms (ArNH3 + ) and the dissociation constant (pKa) of the latter depends on the relative position of the NH2 group and other substituents, AMeO and ANO2 in the present case, on the aromatic ring. The pKa values measured herein show that 4-ANAN (pKa 3.50) will be more protonated and hence more soluble than 2-ANAN (pKa 2.55) in distilled water (pH 5.5). As for DAAN (pKa1 = 2.61; pKa2 = 5.46) half of the chemical is expected to be monoprotonated at the water pH of 5.5, thus explaining its markedly higher water solubility. TNT was the least soluble of all chemicals (0.15 g/ L).

Conclusions:

Solubility of 2,4-dinitroanisole is 0.213 g/L at 25°C, pH 5.5

Executive summary:

Key initial abiotic and biotic reaction routes and determined relevant physicochemical parameters (pK_a, logK_ow, aqueous solubility (S_w), partition coefficient (K_d)) for DNAN and its products were investigated. Reduction of DNAN with either zero valent iron or bacteria regioselectively produced 2-amino-4-nitroanisole (2-ANAN) which, under strict anaerobic conditions, gave 2,4-diaminoanisole (DAAN). Hydrolysis under environmental conditions was insignificant whereas photolysis gave photodegradable intermediates 2-hydroxy-4-nitroanisole and 2,4-dinitrophenol. Physicochemical properties of DNAN and its amino products drastically depended on the type and position of substituent(s) on the aromatic ring. S_w followed the order (TNT < DNAN < 2-ANAN < 4-ANAN < DAAN) whereas logKow followed the order (DAAN < 4-ANAN < 2-ANAN < DNAN < TNT). In soil, successive replacement of ANO₂ by ANH₂ in DNAN enhanced irreversible sorption and reduced bioavailability under oxic conditions.

Following a previously published method (Monteil-Rivera et al, 2004) Solubility of 2,4-dinitroanisole is 0.213 g/L at 25°C, pH 5.5

Description of key information

For this endpoint 2 different independent sources of data were provided Every information provided is relevant for this endpoint, even if the information from each single source alone could be judged insufficient, as these studies did not followed strictly established guidelines, under GLP conditions.

Despite, a strong consistency in the results presented in both studies used for this endpoint was noticed, leading to conclude that combined weight is substantial for allowing an expert judgement.

In fact, every studies presented for this endpoint, not following strictly established guidelines, but these studies all concluded on the same key value: solubility of the substance (i.e. 2,4 -dinitroanisole) is 0.2145 g/L (i.e. the mean of 0.213 and 0.216 g/L).

Key value for chemical safety assessment

Water solubility:

0.214 g/L

at the temperature of:

25 °C