thionyl chloride

chemical compound

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July 14, 2026

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Thionyl chloride (SOCl₂) is a chemical compound used in organic synthesis. It is particularly useful for converting carboxylic acids into acyl chlorides. This reaction is advantageous because the gaseous byproducts, hydrogen chloride (HCl) and sulfur dioxide (SO₂), are easily removed, simplifying the isolation of the acyl chloride. Acyl chlorides are reactive intermediates that can then be used to synthesize other acid derivatives like esters and amides. Thionyl chloride is a type of acid halide, derived from sulfurous acid. It is a pungent, corrosive liquid.123

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carboxylic acid
Conversion to acid derivatives
…of a carboxylic acid with thionyl chloride, SOCl₂ (often in the presence of an amine such as pyridine, C₅H₅N), converts the carboxyl group to the corresponding acyl chloride (RCOOH → RCOCl).
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…of a carboxylic acid with thionyl chloride, SOCl₂ (often in the presence of an amine such as pyridine, C₅H₅N), converts the carboxyl group to the corresponding acyl chloride (RCOOH → RCOCl).
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sulfur
Compounds
Thionyl chloride, SOCl₂, is a dense, toxic, volatile liquid used in organic chemistry to convert carboxylic acids and alcohols into chlorine-containing compounds. Sulfuryl chloride, SO₂Cl₂, is a liquid of similar physical properties utilized in the preparation of certain compounds that contain sulfur, chlorine, or both.
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Thionyl chloride, SOCl₂, is a dense, toxic, volatile liquid used in organic chemistry to convert carboxylic acids and alcohols into chlorine-containing compounds. Sulfuryl chloride, SO₂Cl₂, is a liquid of similar physical properties utilized in the preparation of certain compounds that contain sulfur, chlorine, or both.
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battery
Lithium batteries
Thionyl chloride, a very corrosive and toxic chemical, serves not only as the electrolyte solvent but also as the cathode material. Formation of a film of lithium chloride salt on the lithium prevents a runaway reaction between the lithium anode and the adjacent liquid cathode…
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Thionyl chloride, a very corrosive and toxic chemical, serves not only as the electrolyte solvent but also as the cathode material. Formation of a film of lithium chloride salt on the lithium prevents a runaway reaction between the lithium anode and the adjacent liquid cathode…
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