thioaldehyde

chemical compound

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July 14, 2026

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A thioaldehyde, also known as a thial, is an organic chemical compound that contains a thiocarbonyl functional group (-C(=S)-). This group is analogous to the carbonyl group found in aldehydes and ketones. The parent compound, thioformaldehyde (CH₂=S), is highly reactive and cannot be isolated in standard conditions, though it is stable in low concentrations in the gas phase and has been detected in interstellar space. Thioaldehydes are typically deeply colored and reactive due to the poor overlap between the carbon 2p and sulfur 3p orbitals in their double bond.12

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organosulfur compound
Thiocarbonyl compounds
…carbonyl group, is found in thioaldehydes and thioketones, as well as in a variety of compounds with nitrogen or oxygen (or both) attached to the thiocarbonyl carbon (e.g., ―XC(=S)Y―, where X and Y = N or O). These compounds are named by analogy with the corresponding oxygen compounds—e.g., thioacetone, CH₃C(=S)CH₃,…
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…carbonyl group, is found in thioaldehydes and thioketones, as well as in a variety of compounds with nitrogen or oxygen (or both) attached to the thiocarbonyl carbon (e.g., ―XC(=S)Y―, where X and Y = N or O). These compounds are named by analogy with the corresponding oxygen compounds—e.g., thioacetone, CH₃C(=S)CH₃,…
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