Диметилэтаноламин

Химические свойства

colorless or slightly yellow liquid with ammonia odor. It is miscible with water, ethanol, benzene, ether and acetone.

Использование

2-Dimethylaminoethanol (deanol, DMAE) may be employed as a ligand in the copper-catalyzed amination of aryl bromides and iodides.

Подготовка

The synthesis of 2-Dimethylaminoethanol by the ethylene oxide method is obtained by the ammonification of dimethylamine with ethylene oxide, which is distilled, refined and dehydrated.

Определение

ChEBI: N,N-dimethylethanolamine is a tertiary amine that is ethanolamine having two N-methyl substituents. It has a role as a curing agent and a radical scavenger. It is a tertiary amine and a member of ethanolamines.

Методы производства

Synthesis of dimethylaminoethanol can be accomplished from equimolar amounts of ethylene oxide and dimethylamine (HSDB 1988).

Общее описание

A clear colorless liquid with a fishlike odor. Flash point 105°F. Less dense than water. Vapors heavier than air. Toxic oxides of nitrogen produced during combustion. Used to make other chemicals.

Реакции воздуха и воды

Flammable. Partially soluble in water and less dense than water.

Профиль реактивности

DIMETHYLAMINOETHANOL is an aminoalcohol. Amines are chemical bases. They neutralize acids to form salts plus water. These acid-base reactions are exothermic. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides. N,N-Dimethylethanolamine may react vigorously with oxidizing materials.

Угроза здоровью

Dimethylaminoethanol is classified as a mild skin irritant and a severe eye irritant (HSDB 1988). Doses as high as 1200 mg daily produce no serious side effects and a single dose of 2500 mg taken in a suicide attempt had no adverse effects (Gosselin et al 1976). Inhalation of the vapor or mist can cause irritation to the upper respiratory tract. Asthmatic symptoms have been reported. Extremely irritating; may cause permanent eye injury. Corrosive; will cause severe skin damage with burns and blistering. Ingestion may cause damage to the mucous membranes and gastrointestinal tract. No reports were found in the literature regarding carcinogenic or mutagenic potential.

Промышленное использование

Dimethylaminoethanol is used as a chemical intermediate for antihistamines and local anesthetics; as a catalyst for curing epoxy resins and polyurethanes; and as a pH control agent for boiler water treatment. However, dimethylaminoethanol in the salt form, (i.e. dimethylaminoethanol acetamidobenzoate) is primarily utilized therapeutically as an antidepressant (HSDB 1988).

Профиль безопасности

Moderately toxic by ingestion, inhalation, skin contact, intraperitoneal, and subcutaneous routes. A skin and severe eye irritant. Used medically as a central nervous system stimulant. Flammable liquid when exposed to heat or flame; can react vigorously with oxidzing materials. Ignites spontaneously in contact with cellulose nitrate of high surface area. To fight fire, use alcohol foam, foam, CO2, dry chemical. When heated to decomposition it emits toxic fumes of NOx

Метаболизм

When administered orally, dimethylaminoethanol acetamidobenzoate (the therapeutic salt formulation) has been shown to cross the blood-brain barrier (HSDB 1988). Two other studies have examined the pharmacokinetics of dimethylaminoethanol in rats (Dormand et al 1975) and healthy adults (Bismut et al 1986).
It has been postulated that dimethylaminoethanol undergoes endogenous methylation (LaDu et al 1971). After intravenous treatment of mice with [¹⁴C]-labeled dimethylaminoethanol in the brain, dimethylaminoethanol yielded phosphoryldimethylaminoethanol and phosphatidyldimethylaminoethanol. Acid-soluble and lipid cholines derived from dimethylaminoethanol also were found in brain (Miyazaki et al 1976). While examining the pharmacokinetics of the maleate acid of [¹⁴C]-dimethylaminoethanol in rats, Dormand et al (1975) observed that dimethylaminoethanol was metabolized in the phospholipid cycle and produced metabolites such as phosphoryldimethylaminoethanolamine, and glycerophosphatidylcholine. In kainic-acid lesioned rats, dimethylaminoethanol was converted to a substance which cross-reacted in the radioenzymatic assay for acetylcholine (London et al 1978). Ansell and Spanner (1979) demonstrated that [¹⁴C]-dimethylaminoethanol rapidly disappeared from brain; after 0.5, 1, and 7 h, only 30, 27, and 16% of the administered radioactivity, respectively, remained in the brain after intracerebral injection. They also showed that brain levels of phosphodimethylaminoethanol increased to a maximum at 1-2 h and decreased afterwards, whereas concentrations of phosphatidylethanolamine increased continuously throughout the 7 h observation period. This study further found that after i.p. injections of labeled dimethylaminoethanol, the brain content of phosphatidylethanolamine increased through the 7 h period and the levels were 10-40 fold higher than those of phosphodimethylaminoethanol.

Методы очистки

Dry the amine with anhydrous K2CO3 or KOH, and fractionally distil it. [Beilstein 4 IV 1424.]