Dimethylamine

Dimethylamine is an organic compound with the formula (CH3)2NH[1]. It is a colorless, flammable gas with an ammonia-like odor and is commonly encountered commercially as a solution in water at concentrations up to around 40%[1]. Dimethylamine is a weak base and reacts with acids to form salts[1]. It is produced by catalytic reaction of methanol and ammonia at elevated temperatures and high pressure[1].

Dimethylamine is found widely distributed in animals and plants and is present in many foods at the level of a few mg/kg[1]. It is a precursor to several industrially significant compounds, including dimethyl dithiocarbamate, dimethylformamide, and dimethylacetamide[1]. Dimethylamine is also used in the production of agrichemicals, pharmaceuticals, and the chemical weapon tabun[1]. It is an attractant for boll weevils[1].

Dimethylamine is not very toxic, but it undergoes nitrosation to give dimethylnitrosamine, a carcinogen[1]. The revised IDLH (Immediately Dangerous to Life or Health) for dimethylamine is 500 ppm based on acute inhalation toxicity data in animals[2]. The NIOSH REL (Recommended Exposure Limit) and the current OSHA PEL (Permissible Exposure Limit) for dimethylamine are both 10 ppm (18 mg/m3) TWA (Time-Weighted Average)[2][4].

Dimethylamine is a colorless gas with an ammonia- or fish-like odor[2][4]. It is flammable and has a flash point of 6.7°C (Tagliabue Closed Cup)[3]. The vapour pressure at 25°C is 1292 mmHg[3]. Dimethylamine is soluble in water and has a specific gravity (liquid) of 0.66 at 20°C/4°C[3]. It may produce explosive substances upon contact with mercury and decomposes into toxic gas when burned[3]. Dimethylamine reacts readily with acid and is corrosive to copper, zinc, and their alloys, as well as aluminum[3]. It also reacts with strong oxidizers, chlorine, and nitrite, and affects plastics, rubber, and coating materials[3].

The product standard for dimethylamine includes specifications for monomethylamine, dimethylamine, trimethylamine, ammonia, and water content[3]. Dimethylamine is classified as a high-pressure gas, flammable gas, and acute toxicity material[3]. It is severely irritating to the skin and mucosa upon contact and may cause chemical burns[3]. Repeated exposure may cause CNS disorder, headaches, anemia, elevation of blood pressure, agitation, etc[3]. Inhalation in high concentrations may cause edema of the lungs[3].

For handling dimethylamine, it is recommended to prevent skin contact and eye contact, and to wash skin when contaminated[4]. Respiratory support is advised for breathing difficulties[4]. The NIOSH Pocket Guide to Chemical Hazards provides guidance on respiratory protection, skin protection, and eye protection when handling dimethylamine[4].

Citations:

[1] https://en.wikipedia.org/wiki/Dimethylamine

[2] https://www.cdc.gov/niosh/idlh/124403.html

[3] https://www.mgc.co.jp/eng/products/nc/dimethylamine.html

[4] https://www.cdc.gov/niosh/npg/npgd0219.html

[5] https://www.sigmaaldrich.com/US/en/product/aldrich/295280