Карбонат хлорэтилена

Description

Chloroethylene carbonate (4-chloro-1,3-dioxolan-2-one, cyclic chloroethylene carbonate) is a chlorinated derivative of ethylene carbonate, CAS 3967-54-2, gross formula C3H3ClO3. A key intermediate for the synthesis of vinylene carbonate and fluoroethylene carbonate, the most important electrolyte additives for lithium-ion batteries. In IUPAC nomenclature, the compound also appears as 1,3-dioxolan-2-one, 4-chloro-one, or as cyclic chloroethylene carbonate - both names reflect a five-membered cyclocarbonate ring with a chlorine atom at one of the carbons of the ring.

Basic Attributes

• CAS No.: 3967-54-2
• Chemical formula: C3H3ClO3
• Molecular Weight: 122.51
• Exact weight: 122.51
• EU number: 223-583-5
• NSC Number: 74446
• HS code: 2932999099
• PSA specifications: 35.53000
• XLogP3: -0.73

Physico-chemical characteristics

• Appearance: light yellow liquid
• Density: 1.513 g/cm3 at 25°C
• Boiling point: 212 °C at 735 Torr pressure

Chemical reactivity

The chlorine atom in the ring is in a position activated by the adjacent carbonate fragment, which makes the compound reactive as an electrophile (reacts with nucleophiles by a substitution mechanism) and as a substrate for the elimination of hydrogen chloride under the action of bases - it is the second reaction that underlies the industrial production of vinylene carbonate.

Scope of application

The main purpose of chlorethylene carbonate is the synthesis of vinylene carbonate: under the influence of tertiary amines (in particular, triethylamine) hydrogen chloride is eliminated from cyclic chlorethylene carbonate to form vinylene carbonate, which is introduced into the electrolyte of lithium-ion batteries to form a stable protective layer (SEI) on the surface of the anode. By the same logic, fluoroethylene carbonate is obtained from chloroethylene carbonate, another common electrolyte additive. In addition to battery chemistry, the compound is used as a solvent and intermediate in the synthesis of other fine chemicals. Vinylene carbonate and fluoroethylene carbonate are film-forming electrolyte additives: their molecules are reduced on the surface of the graphite anode before the main electrolyte solvent, forming a thin stable layer (SEI - solid electrolyte interphase), which protects the electrode from further decomposition of the electrolyte and significantly extends the service life and cycling stability of the battery.

Safety Information

The flash point section of the dump ends at the word "Flash" without a numeric value - this fragment is not an independent fact and is not transferred as a number. The source does not contain any other information about transport codes, hazard class codes or GHS phrases H and P.

Storage and transportation conditions

As a chlorinated cyclic carbonate, the substance is sensitive to moisture and is capable of hydrolyzing to release hydrogen chloride. Store in a tightly sealed container in a dry, cool, well-ventilated area, away from water, bases and strong nucleophiles with which the reagent can react at the chlorinated carbon atom. The light yellow color of the fresh product is not a sign of decomposition - it is the natural color of technical chloroethylene carbonate, distinguishing it from the colorless original ethylene carbonate.