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| Names | |||
|---|---|---|---|
| Preferred IUPAC name 2-[(1R)-4-Methylcyclohex-3-en-1-yl]propane-2-thiol | |||
| Other names grapefruit mercaptan 1-p-menthene-8-thiol α,α,4-trimethylcyclohex-3-ene-1-methane thiol thioterpineol | |||
| Identifiers | |||
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3D model (JSmol) | |||
| ChemSpider |
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| ECHA InfoCard | 100.072.886 | ||
| EC Number |
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| UNII | |||
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| Properties | |||
| C10H18S | |||
| Molar mass | 170.31 g/mol | ||
| Density | 1.03 g/cm3 | ||
| Melting point | < 25 °C (77 °F; 298 K) | ||
| Boiling point | 58 °C (136 °F; 331 K) at .33 mmHg | ||
| Hazards | |||
| GHS labelling: | |||
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| Warning | |||
| H302,H315,H319 | |||
| P264,P270,P280,P301+P312,P302+P352,P305+P351+P338,P321,P330,P332+P313,P337+P313,P362,P501 | |||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Grapefruit mercaptan is a naturalorganic compound found ingrapefruit. It is amonoterpenoid that contains athiol (also known as a mercaptan)functional group.Structurally ahydroxy group ofterpineol is replaced by the thiol in grapefruit mercaptan, so it also calledthioterpineol. Volatile thiols typically have very strong, oftenunpleasant odors that can be detected by humans in very low concentrations. Grapefruit mercaptan has a very potent, but not unpleasant, odor, and it is the chemical constituent primarily responsible for the aroma of grapefruit.[1] This characteristic aroma is a property of only theR enantiomer.[2]
Pure grapefruit mercaptan, or citrus-derived oils rich in grapefruit mercaptan, are sometimes used inperfumery and the flavor industry to impart citrus aromas and flavors. However, both industries actively seek substitutes for grapefruit mercaptans for use as a grapefruitflavorant, since its decomposition products are often highly disagreeable to the human sense of smell.
The detection threshold for the (+)-(R) enantiomer of grapefruit mercaptan is 2×10−5 ppb, or equivalently a concentration of 2×10−14. This corresponds to being able to detect 2×10−5 mg in one metric ton of water - one of the lowest detection thresholds ever recorded for a naturally occurring compound.[3]
