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EC number: 248-642-2 | CAS number: 27761-26-8
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Hydrolysis
Administrative data
- Endpoint:
- hydrolysis
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Study period:
- 11-2017
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study with acceptable restrictions
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 017
- Report date:
- 2017
Materials and methods
Test guideline
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 111 (Hydrolysis as a Function of pH)
- Deviations:
- yes
- Remarks:
- substance prepared in situ in acidic solution. At t0 the solution was neutralized to pH 7 and test was started
- Principles of method if other than guideline:
- The study was performed according to the principles described in the guideline, i.e. preliminary screening at 50°C and assessment of hydrolysis at 20°C and neutral pH. Unlike the OECD guideline, only pH 7 was tested. Moreover, due to the instability of the substance, the substance was made in situ by a diazotization reaction. The resulting acidic solution containing the newly formed diazonium salt was neutralized to pH 7 on t0 and the test was started.
- GLP compliance:
- no
Test material
- Reference substance name:
- 2-methoxy-4-nitrobenzenediazonium
- EC Number:
- 248-642-2
- EC Name:
- 2-methoxy-4-nitrobenzenediazonium
- Cas Number:
- 27761-26-8
- Molecular formula:
- C7H6N3O3
- IUPAC Name:
- 2-methoxy-4-nitrobenzenediazonium
Constituent 1
- Specific details on test material used for the study:
- IN SITU SYNTHESIS OF THE DIAZONIUM SALT
2-methoxy-4-nitroaniniline (CAS 97-52-9) was converted in a diazotisation reaction to its corresponding diazonium salt.
1) 2-methoxy-4-nitroaniniline (13.5 g) was suspended in mixture of 25 mL water and 21.3 mL 30 % HCl at 0°C.
2) The mixture was cooled in an ice bath to 0°C and stirred for 30 min
3) A pre-cooled 30 % aq. solution of NaNO2 (80 mmol) was added dropwise over 2h to induce the diazotisation reaction. This reaction is highly exothermic and needs to be carried out carefully. The internal temperature was continuously monitored and maintained below 5°C.
4) Afterwards, the reaction mixture was diluted with water (100 mL) and stirred for another 30 minutes and kept at 0°C.
5) The products were not isolated, but kept in this aqueous solution in an ice bath. The hydrolysis experiments were immediately started. - Radiolabelling:
- no
Study design
- Analytical monitoring:
- yes
- Remarks:
- LC-UV-MS
- Details on sampling:
- Pre-test at 50°C:
- Sampling intervals: 5 days
Main test at 20°C:
- Sampling intervals: 0, 3, 6, 12, 24, 48, 72, 96, 120 h
- Sampling method: vials from which sample was taken were not used anymore after sampling
- Sampling intervals/times for pH measurements: pH measurement at test start
- Sampling intervals/times for sterility check: not performed
- Sample treatment: filtered in case of precipitation or diluted in 1:5 methanol
- Sample storage conditions before analysis: direct analysis - Buffers:
- phosphate buffer 0.1M at pH 7
- Details on test conditions:
- TEST SYSTEM
- Type, material: glass test flasks and vials
- Sterilisation method: none
- Lighting: none
- Measures taken to avoid photolytic effects: incubation in the dark
- Temperature: pre-test at 50°C and main test at 20°C in thermostated oven
TEST MEDIUM
- Preparation of test medium: synthesis solution with concentration 60 mg/mL dissolved 1:30 in 0.1 M phosphate buffer of pH 7
- For main test at 20°C: synthesis solution divided over 20 separate vials
- Renewal of test solution: samples were not disturbed during hydrolysis period
OTHER TEST CONDITIONS
- Adjustment of pH: after dissolution, pH was checked
Duration of test
- Duration:
- 120 h
- pH:
- 7
- Temp.:
- 20 °C
Results and discussion
- Preliminary study:
- After 5 days, significant amount of precipitation, which is removed by filtering. Dilution of 1:10 in MeOH dissolved precipitation.
Degradation after 5 days at 50°C was complete. - Transformation products:
- yes
Identity of transformation products
- No.:
- #1
Reference
- Reference substance name:
- Unnamed
- Molecular formula:
- C7H7N2O2Cl
- Molecular weight:
- 151
Dissipation DT50 of parent compound
- pH:
- 7
- Temp.:
- 20 °C
- DT50:
- < 12 h
- Details on results:
- see any other information on results incl.tables
Any other information on results incl. tables
Main experiment at 20°C
- The concentration of diazonium salt was found to drop quickly to 20 % of the starting concentration after 12h. After 72h, complete hydrolysis is assumed as no parent diazonium salt is left in the reaction mixture.
- The nitro functional group in combination with the diazo functional group are most labile in the molecule.
- The main degradation product is 2 -methoxy-4 -hydroxybenzenediazonium chloride: ca. 26 % after 48h.
- It was expected that the corresponding phenol (substitution of diazogroup by OH) would be the main degradation product, but this could not be confirmed.
- The analysis at t0 shows that the diazotization reaction does not proceed very cleanly with many side products showing at the start of the hydrolysis experiment. The main side product formed is 2 -nitroanisole.
- For additional information (graphs) we refer to the assessment entity report in section 13.
Applicant's summary and conclusion
- Validity criteria fulfilled:
- not applicable
- Conclusions:
- The 2-methoxy-4-nitrobenzenediazonium chloride was found to rapidly hydrolyse. The half-life at 20°C and pH 7 is < 12h. The main degradation product formed is another diazonium salt: 2-methoxy-4-hydroxybenzenediazonium chloride.
- Executive summary:
The hydrolysis of the diazonium salt 2-methoxy-4-nitrobenzenediazonium chloride was investigated in a study based on the principles of OECD 111. Deviation compared to the guideline was needed since the diazonium salt had to be generated in situ due to it's reactivity and explosive properties when isolated.
First,2-methoxy-4-nitroaniniline (CAS 97-52-9) was converted in a diazotisation reaction to its corresponding diazonium salt, 2-methoxy-4-nitrobenzenediazonium chloride. This acidic cooled solution was neutralized to pH 7 in a phosphate buffer. This was considered to be t0 of the experiment.
In the main study at 20°C, the hydrolysis was followed by sampling after 0, 3, 6, 12, 24, 48, 72, 96 and 120h. Samples were filtered or diluted in methanol (1:5) and directly measured by LC-UV-MS. This analysis allowed a semi-quantitative analysis of the degradation products.
The concentration of diazonium salt was found to drop quickly to 20 % of the starting concentration after 12h. After 72h, complete hydrolysis is assumed as no parent diazonium salt is left in the reaction mixture.
The nitro functional group in combination with the diazo functional group are most labile in the molecule. The main degradation product is 2 -methoxy-4 -hydroxybenzenediazonium chloride: ca. 26 % after 48h.
The analysis at t0 shows that the diazotization reaction does not proceed very cleanly with many side products showing at the start of the hydrolysis experiment. The main side product formed is 2 -nitroanisole.
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