123-63-7

A clear colorless liquid with a pleasant odor. Flash point 96°F. Melting point 54°F. Less dense than water. Vapors are heavier than air.

PARALDEHYDE(123-63-7) is an aldehyde. This compound is decomposed by light and air, on prolonged storage, to acetaldehyde and acetic acid. Incompatible with alkalis, hydrocyanic acid iodides and oxidizers.

Highly flammable. Slightly soluble in water. Decomposed by light and air, on prolonged storage, to acetaldehyde and acetic acid.

INHALATION AND INGESTION: Irritation, headache, bronchitis, pulmonary edema. Irritating to digestive tract. Hypnotic and analgesic properties. Incoordination and drowsiness, followed by sleep. Larger doses-coma-weak pulse and shallow respiration, cyanosis-death from respiratory paralysis. EYES: irritation-can cause serious injury. SKIN: Dermatitis (skin inflammation).

Paraldehyde(123-63-7) is used primarily in medicine. It is used as a hypnotic agent, in delirium tremens; and in treatment of psychiatric states characterized by excitement when drugs must be given over a long period of time. It also is administered for intractable pain which does not respond to opiates and for basal and obstetrical anesthesia. It is effective against experimentally induced convulsions and has been used in emergency therapy of tetanus, eclampsia, status epilepticus; and poisoning by convulsant drugs. Since it is used primarily in medicine, the chance of accidental human exposure or environmental contamination is low. However, paraldehyde decomposes to acetaldehyde and acetic acid; these compounds have been found to be toxic. In this case, occupational exposure or environmental contamination is possible. Since paraldehyde is prepared from acetaldehyde by polymerization in the presence of an acid catalyst, there exists a potential for adverse effects, although none have been reported in the available literature. It is also used in the manufacture of organic compounds.

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. Medical observation is recommended for 24
48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy.

UN1264 Paraldehyde, Hazard Class: 3; Labels: 3-Flammable liquid.

Vapor or liquid may form explosive mixture with air. Incompatible with strong oxidants, strong acids; alkalis, ammonia, amines, iodides, hydrocyanic acid. Violent reaction with liquid oxygen. Contact with acids form acetaldehyde. Attacks rubber and plastics.

Paraldehyde was first synthesized in 1829 by Wildenbusch and introduced into clinical practice in the United Kingdom by the Italian physician Vincenzo Cervello in 1882. Paraldehyde, a polymer of acetaldehyde, is a clear colorless or slightly yellow transparent liquid with a strong aromatic as well as a disagreeable taste that at low temperatures, it solidifies into a crystalline mass. This agent decomposes with strong into toxic products that may be released into water, soil, or atmosphere.

Paraldehyde has a characteristic aromatic odor and warm, but disagreeable burning taste.

Incineration in added solvent. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal.

Paraldehyde is used as solvent for fats, oils, waxes, rubber and resins; as substitute for acetaldehyde; as intermediate for organic chemicals, dyestuffs, accelerators for vulcanizations, rubber oxidants, etc. Product Data Sheet

Reactant involved in:• ;Modified Sanford reaction1• ;Synthesis of N-arylbenzoquinaldinium derivatives with antimicrobial activity2• ;Hydroformylation of alkenylamines3• ;Studies of molecules with inhibitory activity against HIV-1 integrase4• ;Irregular Wittig reactions for the formation of α-hydroxyketones5

ChEBI: Paraldehyde(123-63-7) is a trioxane that is 1,3,5-trioxane substituted by methyl groups at positions 2, 4 and 6. It has a role as a sedative.

Prepared by the polymerization of acetaldehyde catalyzed by hydrochloric acid and sulfuric acid at medium to high temperatures.

Paral (Forest).

Recognition at 0.02 to 0.025 mg/m3 (air).

Paraldehyde, 2,4,6-trimethyl-1,3,5-trioxane (4.3.2), is a trimeric acetaldehyde which is synthesized by the acid-catalyzed polymerization of acetaldehyde and at moderate and high temperatures [32,33].

Paraldehyde is used in resin manufacture, as a preservative, and in other processes as a solvent. Paraldehyde may enter to the environment via industrial effluents or hospital wastes. Acetaldehyde and acetic acid are two products of degradation of paraldehyde. This compound and its degradation products may be released into water, soil, or atmosphere and then they may be removed from the atmosphere by precipitation.

Wash paraldehyde with water and fractionally distil it. Alternatively, it is purified by drying with anhydrous Na2SO4, then cooled to 5o, and the frozen material is separated by decantation. The solid is distilled (b 121-124o/atm), the distillate is collected, stored over anhydrous Na2SO4 for several days and re-distilled at atmospheric pressure before use [Le Fevre et al. J Chem Soc 290 1950]. The 2r,4c,6t-trimethyl-1,3,5-trioxane has m 14.5o, b 125o/760mm. [Beilstein 19 II 394, 19 III/IV 4715. 19/9 V 112.]