1,3-диоксолан

Химические свойства

Colourless Liquid. Miscible with water, soluble in alcohol, ether and benzene. The azeotrope formed with water, the azeotrope is 70-73°C, and the water content is 6.7%. Decolorize bromine water.

Использование

1,3-Dioxolane is an intermediate for the preparation of Acyclovir (A192400). Also, 1,3-Dioxolane is used in the synthesis of new Vandetanib (V097100) analogs.

прикладной

1,3-Dioxolane (DOXL) is a cyclic ether. It is a green solvent. It undergoes reaction with C60 to afford an epoxide and 1,3-dioxolane derivative. Reaction has been reported to proceed via a diradical mechanism. A mixture of tetra(ethylene glycol) dimethyl ether (TEGDME) and DOXL has been used to compose the binary electrolyte for use in lithium-sulfur battery. Its efficacy as a solvent in a non-aqueous redox flow battery system has been tested. 1,3-Dioxolane may be used in the fabrication of batteries and capacitors. It may be used as one of the co-solvent to prepare the electrolyte for lithium-sulfur batteries.

Определение

ChEBI: 1,3-dioxolane is a cyclic acetal that is pentane in which the carbon atoms at positions 1 and 3 are replaced by oxygen atoms respectively. It is a dioxolane and a cyclic acetal.

Общее описание

A clear colorless liquid. Flash point 35°F. Slightly denser than water. Vapors heavier than air.

Реакции воздуха и воды

Highly flammable. When exposed to air 1,3-Dioxolane undergoes autooxidation with formation of peroxides. In the distillation process peroxides will concentrate causing violent explosion. Soluble in water.

Профиль реактивности

Ethers, such as 1,3-Dioxolane, can act as bases. They form salts with strong acids and addition complexes with Lewis acids. The complex between diethyl ether and boron trifluoride is an example. Ethers may react violently with strong oxidizing agents. In other reactions, which typically involve the breaking of the carbon-oxygen bond, ethers are relatively inert.

Угроза здоровью

The acute inhalation and oral toxicity of1,3-dioxolane is low in test animals. Thevapor is irritant to eyes and respiratory tract.Application of the liquid produced severeirritation in rabbits’ eyes and mild action onthe animals’ skin. The information on thetoxicity of this compound in humans is notknown.
The inhalation LC50 value of 4-hour exposurein rats is in the range of 20,000 mg/m³,and the oral LD50 is 3000 mg/kg (NIOSH1986).

Пожароопасность

HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.

Промышленное использование

1,3-Dioxolane is used to dissolve a wide spectrum of polymeric materials such as acrylates, alkyds, cellulosics, epoxies, polycarbonates, polyesters, urethanes, and vinyl resins. In many cases, 1,3-dioxolane solvent can replace the chlorinated solvents that were used previously to dissolve many of these polymers. The excellent solvency of 1,3-dioxolane for polymeric compositions makes this cyclic ether a valuable component in paint remover formulations. 1,3-Dioxolane is used to treat polyester fibers for improved dye retention, application of cross-linking agents to cellulosic fibers, and bonding of acrylonitrile polymers. 1,3-Dioxolane is used in metal working and electroplating formulations, as a complexing solvent for organometallic and inorganic salts, and in the preparation of lithium battery electrolyte solutions. 1,3-Dioxolane is a valuable reactant in the polymerization reactions to produce polyacetals. Polymerization reactions of dioxolane with itself or with aldehydes and ethers are catalyzed by a Lewis acid to yield the polyacetal polymers. The methylene group (CH2) bonded to the two oxygen atoms in dioxolane is susceptible to radical abstraction of a hydrogen atom and the resultant dioxolane radical species can be added across various double bond configurations.

Профиль безопасности

Moderately toxic by ingestion and intraperitoneal routes. Mildly toxic by skin contact and inhalation. A shin and severe eye irritant. Mutation data reported. A very dangerous fire hazard when exposed to heat or flame; can react with oxidizers. Used in lithium batteries. Potentially explosive reaction with lithium perchlorate. When heated to decomposition it emits acrid smoke and irritating fumes.

Методы очистки

Dry it with solid NaOH, KOH or CaSO4, and distil it from sodium or sodium amalgam. Barker et al. [J Chem Soc 802 1959] heated 34mL of dioxalane under reflux with 3g of PbO2 for 2hours, then cooled and filtered. After adding xylene (40mL) and PbO2 (2g) to the filtrate, the mixture is fractionally distilled. Addition of xylene (20mL) and sodium wire to the main fraction (b 70-71o) led to a vigorous reaction, following which the mixture was again fractionally distilled. Xylene and sodium additions are made to the main fraction (b 73-74o) before it is finally distilled. [Beilstein 19/1 V 6.]