Vinylene carbonate (VC) or 1,3-dioxol-2-one, is the simplest unsaturated cyclic
carbonic acid ester. Vinylene carbonate can also be thought of as the cyclic carbonate of the hypothetical (''Z'')-ethene-1,2-diol. The
activated double bond in this five-membered oxygen-containing heterocycle makes the molecule a reactive
monomer
In chemistry, a monomer ( ; ''mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization.
Classification
...
for
homopolymerization
A polymer (; Greek ''poly-'', "many" + ''-mer'', "part")
is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and ...
and
copolymerization
In polymer chemistry, a copolymer is a polymer derived from more than one species of monomer. The polymerization of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are some ...
and a dienophile in
Diels-Alder reactions. Below room temperature vinylene carbonate is a colorless stable solid.
Preparation
Since its first description in 1953,
ethylene carbonate
Ethylene carbonate (sometimes abbreviated EC) is the organic compound with the formula (CH2O)2CO. It is classified as the cyclic carbonate ester of ethylene glycol and carbonic acid. At room temperature (25 °C) ethylene carbonate is a tra ...
has been commonly used as starting material for vinylene carbonate. In the first stage,
monochlorethylene carbonate is produced in a UV-initiated
photochlorination
Photochlorination is a chlorination reaction that is initiated by light. Usually a C-H bond is converted to a C-Cl bond. Photochlorination is carried out on an industrial scale. The process is exothermic and proceeds as a chain reaction initiated ...
reaction with chlorine or
sulfuryl chloride
Sulfuryl chloride is an inorganic compound with the formula SO2Cl2. At room temperature, it is a colorless liquid with a pungent odor. Sulfuryl chloride is not found in nature, as can be inferred from its rapid hydrolysis.
Sulfuryl chloride is ...
at 60-70 °C in bulk. In the second stage, monochlorethylenecarbonate undergoes dehydrochlorination with a base such as
triethylamine
Triethylamine is the chemical compound with the formula N(CH2CH3)3, commonly abbreviated Et3N. It is also abbreviated TEA, yet this abbreviation must be used carefully to avoid confusion with triethanolamine or tetraethylammonium, for which TEA ...
.
:

Instead of in the liquid phase, the dehydrochlorination may also be carried out in the gas phase on a
zinc chloride
Zinc chloride is the name of inorganic chemical compounds with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, and are highly soluble in water. This salt is hygroscopic and e ...
impregnated catalyst in a
fluidized bed
A fluidized bed is a physical phenomenon that occurs when a solid particulate substance (usually present in a holding vessel) is under the right conditions so that it behaves like a fluid. The usual way to achieve a fluidize bed is to pump pressur ...
reactor at 350-500 °C. The seemingly simple reaction yields only 70 to 80% of impure end product due to a variety of side reactions. For example, in the chlorination of ethylene carbonate in substance or solution,
2-chloroacetaldehyde
Chloroacetaldehyde is an organic compound with the formula ClCH2CHO. Like some related compounds, it is highly electrophilic reagent and a potentially dangerous alkylating agent. The compound is not normally encountered in the anhydrous form, b ...
, polychlorinated ethylene carbonate and chlorinated
ring-opening products are formed besides others. The separation of the by-products from the final product by distillation by
thin-film evaporator
A thin film is a layer of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. The controlled synthesis of materials as thin films (a process referred to as deposition) is a fundamental step in many ap ...
,
[ ]fractional recrystallization
In chemistry, fractional crystallization is a method of refining substances based on differences in their solubility. It fractionates via differences in crystallization (forming of crystals). If a mixture of two or more substances in solutio ...
or zone melting
Zone melting (or zone refining, or floating-zone method, or floating-zone technique) is a group of similar methods of purifying crystals, in which a narrow region of a crystal is melted, and this molten zone is moved along the crystal. The molte ...
is very expensive. The content of by-products can be reduced by stirring with sodium borohydride
Sodium borohydride, also known as sodium tetrahydridoborate and sodium tetrahydroborate, is an inorganic compound with the formula Na BH4. This white solid, usually encountered as an aqueous basic solution, is a reducing agent that finds applic ...
or urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid.
Urea serves an important ...
at elevated temperature. However, the purification is complicated by the pronounced thermolability of vinylene carbonate, as it decomposes at temperatures above 80 °C within minutes.[ Highly pure vinylene carbonate can be obtained in yields of more than 70% by optimizing the chlorination conditions to suppress the formation of by-products][ and a combination of several gentle purification processes. The tendency of the liquid vinylene carbonate to polymerize is suppressed by addition of inhibitors such as butylhydroxytoluene (BHT).
]
Properties
Industrially produced vinylene carbonate is usually a yellow to brown liquid. By suitable process control and purification steps, a solid product with a melting point of 20-22 °C and a chlorine content below 10ppm can be obtained. Liquid vinylene carbonate turns rapidly yellow even in the absence of light and must be stabilized by the addition of radical scavengers. In solid form, the highly pure substance is long-term stable when stored below 10 °C. Vinylene carbonate dissolves in a variety of solvents such as ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a h ...
, tetrahydrofuran, ethylene carbonate, propylene carbonate, and other dipolar aprotic electrolyte solvents used for lithium ion rechargeable batteries such as dimethyl carbonate, diethyl carbonate
Diethyl carbonate (sometimes abbreviated DEC) is an ester of carbonic acid and ethanol with the formula OC(OCH2CH3)2. At room temperature (25 °C) diethyl carbonate is a colorless liquid with a low flash point.
Diethyl carbonate is used as ...
and the like.
Use
The first publication on vinylene carbonate described its Diels-Alder reaction using the example of its addition reaction
In organic chemistry, an addition reaction is, in simplest terms, an organic reaction where two or more molecules combine to form a larger one (the adduct)..
Addition reactions are limited to chemical compounds that have multiple bonds, such as ...
with 2,3-dimethylbutadiene to a bicyclic carbonate and subsequent hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile.
Biological hydrolysis ...
to cis-4,5-dihydroxy-1,2-cyclohexene:[
:]
When cyclopentadiene
Cyclopentadiene is an organic compound with the formula C5H6.LeRoy H. Scharpen and Victor W. Laurie (1965): "Structure of cyclopentadiene". ''The Journal of Chemical Physics'', volume 43, issue 8, pages 2765-2766. It is often abbreviated CpH beca ...
is used as the diene
In organic chemistry a diene ( ) (diolefin ( ) or alkadiene) is a covalent compound that contains two double bonds, usually among carbon atoms. They thus contain two alk''ene'' units, with the standard prefix ''di'' of systematic nomenclature ...
, the vicinal norbornene diol bicyclo .2.1ept-5-ene-2,3-diol is formed after hydrolysis. The Swern oxidation
The Swern oxidation, named after Daniel Swern, is a chemical reaction whereby a primary or secondary alcohol is oxidized to an aldehyde or ketone using oxalyl chloride, dimethyl sulfoxide (DMSO) and an organic base, such as triethylamine. It is on ...
to the 1,2-ketone bicyclo .2.1ept-5-ene-2,3-dione proceeds (in the variant with trifluoroacetic anhydride
Trifluoroacetic anhydride (TFAA) is the acid anhydride of trifluoroacetic acid. It is the perfluorinated derivative of acetic anhydride.
Preparation
Trifluoroacetic anhydride was originally prepared by the dehydration of trifluoroacetic acid with ...
instead of oxalyl chloride
Oxalyl chloride is an organic chemical compound with the formula (COCl)2. This colorless, sharp-smelling liquid, the diacyl chloride of oxalic acid, is a useful reagent in organic synthesis.
Preparation
Oxalyl chloride was first prepared in 189 ...
) with a yield of 73%.
:
Under UV irradiation
Ultraviolet germicidal irradiation (UVGI) is a disinfection method that uses short-wavelength ultraviolet ( ultraviolet C or UV-C) light to kill or inactivate microorganisms by destroying nucleic acids and disrupting their DNA, leaving them unab ...
, ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bon ...
s react with vinylene carbonate to form bicyclic exo-oxetane
Oxetane, or 1,3-propylene oxide, is a heterocyclic organic compound with the molecular formula , having a four-membered ring with three carbon atoms and one oxygen atom.
The term "an oxetane" or "oxetanes" refer to any organic compound containing ...
s:
:
With phosphorus(V)sulfide, vinylene carbonate reacts to the corresponding vinylenethionocarbonate (2-thiono-1,3-dioxol-4-ene), which gives ketene
In organic chemistry, a ketene is an organic compound of the form , where R and R' are two arbitrary monovalent chemical groups (or two separate substitution sites in the same molecule). The name may also refer to the specific compound eth ...
in quantitative yield upon UV irradiation. The reaction is a good alternative to the decomposition
Decomposition or rot is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is ...
of α-diazoketones.
:
Vinylene carbonate is used widely as an electrolyte additive for lithium-ion batteries
A lithium-ion or Li-ion battery is a type of rechargeable battery which uses the reversible reduction of lithium ions to store energy. It is the predominant battery type used in portable consumer electronics and electric vehicles. It also see ...
where it promotes the formation of an insoluble film between the electrolyte and the negative electrode: the SEI (solid-electrolyte-interface). This polymer film allows ionic conduction, but prevents the reduction of the electrolyte at the negative (graphite) electrode and contributes significantly to the long-term stability of lithium-ion batteries. A 2013 publication suggests that the cyclic sultone
In organosulfur chemistry, a sulfonate is a salt or ester of a sulfonic acid. It contains the functional group , where R is an organic group. Sulfonates are the conjugate bases of sulfonic acids. Sulfonates are generally stable in water, non- ...
3-fluoro-1,3-propanesultone (FPS) is superior to vinylene carbonate in SEI formation.
:
Since 1,3-propane sultone
1,3-Propane sultone is the organosulfur compound with the formula (CH2)3SO3. It is a cyclic sulfonate ester, a class of compounds called sultones. It is a readily melting colorless solid.
Synthesis
It may be prepared by the acid catalyzed reacti ...
(on which FPS is based) is classified as a particularly dangerous carcinogenic substance, a significant hazard potential must also be assumed for FPS.
Polymers
Already the first work on vinylene carbonate describes its bulk polymerization a colorless polymer, which hydrolyzes to a water-soluble product.[ Subsequent publications suggest that the first authors produced only low molecular weight oligomers.] The preparation of higher molecular weight polymers with useful properties depends critically on the purity of the vinylene carbonate monomer. Vinylene carbonate can be homopolymerized in bulk
Bulk can refer to:
Industry
* Bulk cargo
* Bulk liquids
* Bulk mail
* Bulk material handling
* Bulk pack, packaged bulk materials/products
* Bulk purchasing
*
Baking
* Bulk fermentation, the period after mixing when dough is left alone to ferm ...
, in solution, in suspension
Suspension or suspended may refer to:
Science and engineering
* Suspension (topology), in mathematics
* Suspension (dynamical systems), in mathematics
* Suspension of a ring, in mathematics
* Suspension (chemistry), small solid particles suspen ...
and in dispersion
Dispersion may refer to:
Economics and finance
* Dispersion (finance), a measure for the statistical distribution of portfolio returns
*Price dispersion, a variation in prices across sellers of the same item
* Wage dispersion, the amount of variat ...
using radical initiator
In chemistry, radical initiators are substances that can produce radical species under mild conditions and promote radical reactions. These substances generally possess weak bonds—bonds that have small bond dissociation energies. Radical i ...
s such as azobis(isobutyronitrile) (AIBN) or benzoyl peroxide
Benzoyl peroxide is a chemical compound (specifically, an organic peroxide) with structural formula , often abbreviated as (BzO)2. In terms of its structure, the molecule can be described as two benzoyl (, Bz) groups connected by a peroxide () ...
. It can also be copolymerized with other vinyl monomers such as vinyl pyrrolidone or vinyl propionate
Vinyl propionate is the organic compound with the formula CH3CH2CO2CH=CH2. This colorless liquid is the ester of propionic acid and vinyl alcohol. It is used to produce poly(vinyl propionate) as well as copolymers with acrylate esters,
vinyl chl ...
.
:
Polyvinylene carbonate is readily soluble in acetone
Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour.
Acetone is miscible wi ...
and dimethylformamide
Dimethylformamide is an organic compound with the formula ( CH3)2NC(O)H. Commonly abbreviated as DMF (although this initialism is sometimes used for dimethylfuran, or dimethyl fumarate), this colourless liquid is miscible with water and the maj ...
. The solutions obtained, however, tend to decompose already at room temperature. The patent literature describes the use of polyvinyl carbonate for strong fibers, clear, colorless and mechanically strong films,[ membranes for ]reverse osmosis
Reverse osmosis (RO) is a water purification process that uses a partially permeable membrane to separate ions, unwanted molecules and larger particles from drinking water. In reverse osmosis, an applied pressure is used to overcome osmotic ...
and as support during affinity chromatography
Affinity chromatography is a method of separating a biomolecule from a mixture, based on a highly specific macromolecular binding interaction between the biomolecule and another substance. The specific type of binding interaction depends on the ...
.
In addition to the instability in solutions, polyvinyl carbonate has the tendency towards hydrolysis in weakly alkaline medium. This forms polyhydroxymethylene (PHM) via cleavage of the cyclic carbon ring, with the repeating unit –(CHOH)–. Its behavior is much more similar to cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...
than to the structurally related polyvinyl alcohol
Poly(vinyl alcohol) (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula H2CH(OH)sub>''n''. It is used in papermaking, textile warp sizing, as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) ...
with the repeating unit –(CH2–CHOH)–.
:
For example, polyhydroxymethylene films obtained by alkaline hydrolysis of polyvinylene carbonate films via sodium methoxide
Sodium methoxide is the simplest sodium alkoxide. With the formula , it is a white solid, which is formed by the deprotonation of methanol. Itis a widely used reagent in industry and the laboratory. It is also a dangerously caustic base. ...
in methanol are crystalline and exhibit high tensile strengths.[ Analogous to cellulose, polyhydroxymethylene can be dissolved in hot sodium hydroxide solution and converted by crosslinking into a highly swellable polymer which can take up to 10,000 times its weight in water. Polyhydroxymethylene is soluble in anhydrous ]hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly toxic unless handled in solution as, for example, hydrazin ...
and can be converted into cellulose-like fibers by spinning in water. Similar to cellulose, polyhydroxymethylene reacts with carbon disulfide
Carbon disulfide (also spelled as carbon disulphide) is a neurotoxic, colorless, volatile liquid with the formula and structure . The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical ...
in the alkaline state to form a xanthate
150px, Sodium salt of ethyl xanthate
Xanthate usually refers to a salt with the formula (R = alkyl; M+ = Na+, K+), thus they are the metal-thioate/''O''-esters of dithiocarbonate. The name ''xanthates'' is derived from Ancient Greek ''xanthos' ...
, from which water-insoluble polyhydroxymethylene is again obtained by precipitation in dilute sulfuric acid.
Safety
Vinylene carbonate requires particular care when handling because of its problematic toxicological and ecotoxicological profile[ and its potential carcinogenic properties.]
References
{{Reflist
Carbonate esters
Oxygen heterocycles