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In organic chemistry, a thiol (, )〔''Dictionary Reference'': (thiol )〕 is an organosulfur compound that contains a carbon-bonded sulfhydryl (–C–SH or R–SH) group (where R represents an alkane, alkene, or other carbon-containing group of atoms). Thiols are the sulfur analogue of alcohols (that is, sulfur takes the place of oxygen in the hydroxyl group of an alcohol), and the word is a portmanteau of "thion" + "alcohol," with the first word deriving from Greek θεῖον ("thion") = "sulfur." The –SH functional group itself is referred to as either a ''thiol group'' or a ''sulfhydryl group''. Many thiols have strong odors resembling that of garlic. Thiols are used as odorants to assist in the detection of natural gas (which in pure form is odorless), and the "smell of natural gas" is due to the smell of the thiol used as the odorant. Thiols are often referred to as ''mercaptans''.〔Patai, Saul “The chemistry of the thiol group” Saul Patai, Ed. Wiley, London, 1974. ISBN 0-471-66949-0.〕〔R. J. Cremlyn “An Introduction to Organosulfur Chemistry” John Wiley and Sons: Chichester (1996). ISBN 0-471-95512-4.〕 The term mercaptan 〔''Dictionary Reference'': (mercaptan )〕 was introduced in 1832 by William Christopher Zeise and is derived from the Latin ''mercurium captans'' (capturing mercury)〔''Oxford American Dictionaries'' (Mac OS X Leopard).〕 because the thiolate group bonds very strongly with mercury compounds.〔"Mercaptan" (ethyl thiol) was discovered in 1834 by the Danish professor of chemistry William Christopher Zeise (1789–1847). He called it "mercaptan", a contraction of "corpus mercurium captans" (mercury-capturing substance) (88 ), because it reacted violently with mercury (II) oxide ("deutoxide de mercure") (92 ). See: * Zeise, William Christopher (1834) ("Sur le mercaptan; avec des observations sur d'autres produits resultant de l'action des sulfovinates ainsi que de l'huile de vin, sur des sulfures metalliques" ) (On mercaptan; with observations on other products resulting from the action of sulfovinates (ethyl hydrogen sulfate ) and oil of wine (mixture of diethylsufate and ethylene polymers ) on metal sulfides), ''Annales de Chimie et de Physique'', 56 : 87–97. * The article in ''Annales de Chimie et de Physique'' (1834) was translated from the German article: W. C. Zeise, ("Das Mercaptan, nebst Bemerkungen über einige neue Producte aus der Einwirkung der Sulfurete auf weinschwefelsaure Salze und auf das Weinöl," ) ''Annalen der Physik und Chemie'', 107 (27) : 369–431. * The article in ''Annalen der Physik und Chemie'' (1834) was translated from the original Danish article in: Zeise (1834) "Mercaptanet med Bemaerkninger over nogle andre nye Producter af Svovelvinsyre saltene, som og af den tunge Vinolle, ved Sulfureter," ''Saertskilt aftrykt af det Kongelige Danske Videnskabers Selskabs Skrifter'' (Special issue of the Journal of the Royal Danish Society of Science), 70 pages. * German translation is reprinted in: W. C. Zeise (1834) "Das Mercaptan, nebst Bemerkungen über einige andere neue Erzeugnisse der Wirkung schwefelweinsaurer Salze, wie auch des schweren Weinöls auf Sulphurete," ''Journal für praktische Chemie'', 1 (1) : 257–268, 345–356, 396–413, 457–475. * Summarized in: Zeise , W. C. (1834), (Ueber das Mercaptan ) (On mercaptan), ''Annalen der Pharmacie'', 11 (1) : 1–10.〕 Thiols react with mercury to form ''mercaptides''.〔(【引用サイトリンク】author=Vibrant Life Magazine, Loren K. )〕 ==Structure and bonding== Thiols and alcohols have similar molecular structure. The major difference is the size of the chalcogenide, C–S bond lengths being around 180 picometers in length and C-O bond lengths being around 143 picometers in length. The C–S–H angles approach 90°. In the solid or molten liquids, the hydrogen-bonding between individual thiol groups is weak, the main cohesive force being van der Waals interactions between the highly polarizable divalent sulfur centers. Due to the lesser electronegativity difference between sulfur and hydrogen compared to oxygen and hydrogen, an S–H bond is less polar than the hydroxyl group. Thiols have a lower dipole moment relative to the corresponding alcohol 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Thiol」の詳細全文を読む スポンサード リンク
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