2,5-ジメチルアニリン

log Kow = 1.83 at pH 7.4

1.83

1.83

0.979 at 70 °F (NTP, 1992) - Less dense than water; will float

0.9790 @ 21 °C/4 °C

Relative density (water = 1): 0.98

YELLOW LEAF FROM PETROLEUM ETHER

Colorless to yellow oil

Yellow liquid or solid

less than 1 mg/mL at 64 °F (NTP, 1992)

Sol in ether, carbon tetrachloride

SLIGHTLY SOL IN ETHANOL

Soluble in oxygenated solvents.

5600 mg/l at 12 °C in water

201 °F (NTP, 1992)

93 °C

417 °F at 760 mmHg (NTP, 1992)

214 °C @ 760 MM HG

218 °C

59.9 °F (NTP, 1992)

15.5 °C

15.5 °C

4.18 (NTP, 1992) - Heavier than air; will sink (Relative to Air)

Relative vapor density (air = 1): 4.19

Odor threshold in air= 1.00X10+12 molecules/cc. /Xylidine/

Threshold for xylidine is 0.0240 mg/cu m /Xylidine/

Danger

H301+H311+H331 (37.6%): Toxic if swallowed, in contact with skin or if inhaled [Danger Acute toxicity, oral; acute toxicity, dermal; acute toxicity, inhalation]

P260, P261, P262, P264, P270, P271, P273, P280, P301+P316, P302+P352, P304+P340, P316, P319, P321, P330, P361+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 101 reports by companies from 11 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Danger

H301 (100%): Toxic if swallowed [Danger Acute toxicity, oral]

Chemical: Benzenamine, 2,5-dimethyl-

Status: Active Update: 24-05-2019 https://echa.europa.eu/registration-dossier/-/registered-dossier/10861

2,5-Dimethylaniline: Does not have an individual approval but may be used under an appropriate group standard

This chemical is combustible. (NTP, 1992)

Combustible. Gives off irritating or toxic fumes (or gases) in a fire. Above 93 °C explosive vapour/air mixtures may be formed.

SYMPTOMS: Symptoms of exposure to this compound may include headaches, drowsiness, cyanosis, mental confusion, anorexia, convulsions, nervous system and blood effects, fatigue, loss of appetite, dizziness and damage to the lungs, liver and kidneys.

The major hazards encountered in the use and handling of 2,5-xylidine stem from its toxicologic properties. Toxic by all routes (ie, inhalation, ingestion, and dermal absorption), exposure to this colorless to yellow oil or leaf may occur from its use as a chemical intermediate for the production of dyes. Contact with 2,5-xylidine may cause burns to the skin and eyes. Death is also a possible outcome from exposure. While the OSHA PEL is set at a TWA of 5 ppm, the ACGIH lists xylidine (mixed isomers) on its 1988-1989 Notice of Intended Changes with a proposed TLV of 0.5 ppm, and a designation of "suspected human carcinogen". In activities or situations where over-exposure may occur, wear a self-contained breathing apparatus, and full chemical protective clothing which is specifically recommended by the shipper or manufacturer to prevent skin contact with xylidine. If contact should occur, immediately flush the affected skin or eyes with running water for at least 15 minutes. Remove contaminated clothing and shoes at the site. Do not eat or smoke in xylidine work areas. While xylidine does not ignite easily, it can burn with the production of irritating or poisonous gases. Also, containers may explode violently in the heat of a fire. Fires involving xylidine may be extinguished with dry chemical, CO2, Halon, or standard foam. Water spray if used, should be applied with caution because it may cause frothing. Fight the fire from a maximum distance and dike runoff from fire control water. Xylidine should be stored away from heat, strong oxidizers, and hypochlorite bleaches. Shipping regulations and other DOT regulatory requirements should be consulted before transport. If xylidine should spill, dike far ahead, then take up with sand or other noncombustible absorbent and place into containers for later disposal. Incineration is a possible form of disposal for xylidine. Before implementing land disposal of waste 2,5-xylidine, consult with environmental regulatory agencies for guidance.

Permissible Exposure Limit: Table Z-1 8-hr Time-Weighted Avg: 5 ppm (25 mg/cu m). Skin Designation. /Xylidine/

Vacated 1989 OSHA PEL TWA 2 ppm (10 mg/cu m), skin designation, is still enforced in some states. /Xylidine/

2,5-XYLIDINE ignites on contact with fuming nitric acid (NTP, 1992). Neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides.

Fires involving this material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher. (NTP, 1992)

Use water spray, carbon dioxide, foam, powder.

Fresh air, rest. Refer for medical attention.

Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention .

Rinse with plenty of water for several minutes (remove contact lenses if easily possible).

Rinse mouth. Refer for medical attention .

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Use water spray, dry chemicsl, foam, or CO2. Wear full protective clothing. /Xylidines/

If material on fire or involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. /Xylidines/

Environmental considerations - land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash, cement powder, or commercial sorbents. /Xylidines/

Environmental considerations - water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses. /Xylidines/

SMALL SPILLS AND LEAKAGE: If you spill this chemical, FIRST REMOVE ALL SOURCES OF IGNITION. Then, use absorbent paper to pick up all liquid spill material. Your contaminated clothing and absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with 60-70% ethanol followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

Disposal methods: incineration. A). Dissolve in such combustible solvent as alcohols, benzene, etc. Spray solvent into the furnace with afterburner and scrubber. B). Pour into a mixture of sand and soda ash (9:1). After mixing, put into a paper carton stuffed full with packing paper to serve as fuel. Burn in the furnace. /Xylidines/

Personal protection: chemical protection suit and filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

Non-impervious clothing which becomes contaminated with xylidine should be removed immediately and not reworn until the xylidine is removed from the clothing. /Xylidines/

Eating and smoking should not be permitted in areas where liquid xylidine is handled, processed, or stored. /Xylidines/

Employees who handle liquid xylidine should wash their hands thoroughly with soap or mild detergent and water before eating, smoking, or using toilet facilities. /Xylidines/

For more Preventive Measures (Complete) data for 2,5-XYLIDINE (7 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 240(SRC), determined from a measured log Kow of 1.83(2) and a recommended regression-derived equation(3), indicates that 2,5-xylidine will have moderate mobility in soil(SRC). However, anilines are expected to bind strongly to humus or soil organic matter in soils due to the high reactivity of the aromatic amino group(4,5), suggesting that mobility may be much lower in some soils(SRC). Volatilization of 2,5-xylidine may be important from moist soil surfaces(SRC) given an estimated Henry's Law constant of 2.5X10-6 atm-cu m/mole(SRC), using a fragment constant estimation method(6). Based on limited aqueous screening study data, 2,5-xylidine may be resistant to aerobic biodegradation in soil(SRC). In the Japanese MITI test 2,5-xylidine reached 0-1% of its theoretical BOD in 4 weeks(7) and was classified as slow to biodegrade(8); both tests used an activated sludge inoculum. In contrast, an activated sludge test reported rapid biodegradation (rate of 3.6 mg COD/g-hr)(9).

AQUATIC FATE: Based on a recommended classification scheme for soil(1), an estimated Koc value of 240(SRC), determined from a measured log Kow of 1.83(2) and a recommended regression-derived equation(3), indicates that 2,5-xylidine should not adsorb to suspended solids and sediment in water(SRC). However, aromatic amine groups are recognized as having a strong affinity to organic carbon, suggesting that this compound may bind strongly to suspended organic material in water(4,5). 2,5-Xylidine may volatilize from water surfaces(3,SRC) based on an estimated Henry's Law constant of 2.5X10-6 atm-cu m/mole(SRC), developed using a fragment constant estimation method(6). Estimated half-lives for a model river and model lake are 16 and 120 days, respectively(3,SRC) although adsorption to organic material may attenuate this process(SRC). As a class, aromatic amines react relatively rapidly in sunlit natural water via reaction with photochemically-produced hydroxyl radicals and peroxy radicals(11); typical half-lives for peroxy and hydroxy radical reactions are on the order of 19 and 30 sunlight hours, respectively(11). According to a classification scheme(7), BCF values ranging from 1.5-3.8(8), measured in carp, suggest that bioconcentration in aquatic organisms is low(SRC). Based on limited aqueous screening study data, 2,5-xylidine may be resistant to aerobic biodegradation in water(SRC). 2,5-Xylidine reached 0-1% of its theoretical BOD in 4 weeks(8) and was classified as slow to biodegrade in the Japanese MITI test(9); both tests used an activated sludge inoculum. In contrast, an activated sludge test reported rapid biodegradation (rate of 3.6 mg COD/g-hr)(10).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,5-xylidine, which has a measured vapor pressure of 0.15 mm Hg at 20 °C(2), should exist solely as a vapor in the ambient atmosphere. Vapor-phase 2,5-xylidine is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be about 2 hours(3,SRC).

Dizziness. Drowsiness. Headache. Nausea.

MAY BE ABSORBED! See Ingestion.

Blue lips, fingernails and skin. Dizziness. Drowsiness. Headache. Nausea. Unconsciousness.

Initial medical examination: A complete history & physical examination. The purpose is to detect existing conditions that might place the exposed employee at increased risk, and to establish a baseline for future health monitoring. Exam of the blood, lungs, liver, kidneys, and cardiovascular system should be stressed. ... Periodic medical exam ... should be repeated on an annual basis. /Xylidine/

The Koc of 2,5-xylidine is estimated as approximately 240(SRC), using a measured log Kow of 1.83(1) and a regression-derived equation(2,SRC). According to a recommended classification scheme(3), this estimated Koc value suggests that 2,5-xylidine has moderate mobility in soil(SRC). However, anilines are expected to bind strongly to humus or soil organic matter in soils due to the high reactivity of the aromatic amino group(4,5). Low adsorption is observed at a neutral pH with pure clay minerals or soils for substituted anilines(5).

2,5-Xylidine, present at 100 mg/L, reached 0-1% of its theoretical BOD in 4 weeks using an activated sludge inoculum(1). In the Japanese MITI test, 2,5-xylidine (present at 100 mg/L) was classified as slow to biodegrade indicating that only 0-29% of the theoretical BOD was reached in 2 weeks using an activated sludge inoculum(2). 2,5-Xylidine, initially present at 200 mg/L COD, reached 96.5% degradation (measured as removal of COD) with a rate of biodegradation of 3.6 mg COD/g-hr using an activated sludge inoculum(3).

2,5-Xylidine

Group 3: Not classifiable as to its carcinogenicity to humans

Volume 16: (1978) Some Aromatic Amines and Related Nitro Compounds – Hair Dyes, Colouring Agents and Miscellaneous Industrial Chemicals

1987

1987

The Henry's Law constant for 2,5-xylidine is estimated as 2.5X10-6 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This value indicates that 2,5-xylidine will volatilize from water surfaces(2,SRC). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec) is estimated as approximately 16 days(2,SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec) is estimated as approximately 120 days(2,SRC). Adsorption to organic material in water may attenuate this process(SRC). 2,5-Xylidine's Henry's Law constant(1,SRC) indicates that volatilization from moist soil surfaces may occur(SRC).

2,5-Xylidine is oxidized mainly to para-amino xylols, eg, 4-hydroxy-2,5-dimethylaniline.

To a small degree, a methyl group of 2,5-xylidine is oxidized to produce 4-methyl-2- aminobenzoic acid and 4-methyl-3-aminobenzoic acid.

2,5-dimethylaniline has known human metabolites that include N-(2,5-Dimethylphenyl)acetamide.

CHEM INT FOR SOLVENT RED 26, DIRECT VIOLET 7

Used as a chemical intermediate for the synthesis of Direct Yellow 51, Solvent Red 22, Solvent Red 26.

Used in the manufacture of p-xyloquinone; Direct Violet 7

p-xylene (nitration/nitro reduction)

Usually obtained by iron reduction of the corresponding nitroxylene.

2,5-Xylidine is produced commercially by the following method: 1) nitrating and reducing commercial xylene to an isomeric mixture of xylidines, 2) after 2,4-xylidine is removed by formation of the acetate salt, 2,5-xylidine hydrochloride is precipitated by the addition of hydrochloric acid and this can be converted to 2,5-xylidine by the addition of base.