Thiosulfinate

Last updated
General structure of a thiosulfinate, drawn in expanded octet style Thiosulfinate-ester-general-2D.png
General structure of a thiosulfinate, drawn in expanded octet style

In organosulfur chemistry, thiosulfinate is a functional group consisting of the linkage R-S(O)-S-R (R refers to organic substituents). Thiolsulfinates are also named as alkanethiosulfinic (or arenethiosulfinic) acid esters.

Contents

They are the first of the series of functional groups containing an oxidized disulfide bond. Other members of this family include thiosulfonates (R-SO2-S-R), α-disulfoxides (R-S(O)-S(O)-R), sulfinyl sulfones (R-S(O)-SO2-R), and α-disulfones (R-SO2-SO2-R), of which all (except αdisulfoxides [2] ) are known. The thiosulfinate group can occur in cyclic as well as acyclic structures. [3] [4] [5]

Occurrence

Allicin R-allicin-2D-skeletal.svg
Allicin

A variety of acyclic and cyclic thiosulfinates are found in plants, or formed when the plants are cut or crushed.

A well-known thiosulfinate is allicin, one of the active ingredients formed when garlic is crushed. Allicin was discovered in 1944 by Chester J. Cavallito and coworkers. Thiosulfinates containing various combinations of the methyl, n-propyl, 1-propenyl, 2-propenyl, n-butyl, 1-butenyl and 2-butenyl groups are formed upon crushing different Allium as well as Brassica species. [6] [7]

Zeylanoxides are cyclic thiosulfinates containing the 1,2-dithiolane-1-oxide ring, isolated from the tropical weed Sphenoclea zeylanica . These heterocyclic thiosulfinates are chiral at carbon as well as at sulfur. [8]

Crushing the roots of Petiveria alliacea affords the thiosulfinates S-(2-hydroxyethyl) 2-hydroxyethane)thiosulfinate, S-(2-hydroxylethyl) phenylmethanethiosulfinate, S-benzyl 2-hydroxyethane)thiosulfinate and S-benzyl phenylmethanethiosulfinate (petivericin; PhCH2S(O)SCH2Ph). [9] Asparagusic acid S-oxide [10] and brugierol [11] are other natural 1,2-dithiolane-1-oxides occurring in Asparagus officinalis and Bruguiera conjugata , respectively.

Properties

Allicin, S-benzyl phenylmethanethiosulfinate, and related thiosulfinates show radical-trapping antioxidant activity associated with easy formation of sulfenic acids [12] The acyclic thiosulfinates from Allium and Brassica species possess antimicrobial, antiparasitic, antitumor and cysteine protease inhibitory activity while the natural 1,2-dithiolane-1-oxides are growth inhibitors. The thiosulfinates from Petiveria also exhibit antimicrobial activity. [13]

Thiosulfinates feature a S(IV) center linked to a S(II) center, the former being stereogenic. Conversion of simple disulfides to thiosulfinates results in a considerable weakening of the S–S bond from about 47.8 to 28.0 kcal mol−1 for the S-S bond in PhS(O)SPh and from about 63.2 to 39.3 kcal mol−1 for the S-S bond in MeS(O)SMe, [14] with the consequence that most thiosulfinates are both unstable and quite reactive. For this reason the mixtures of thiosulfinates from Allium plants can best be separated by HPLC at room temperature rather than by gas chromatography (GC), although GC has been used with some low molecular weight thiosulfinates. Thiosulfinates can be distinguished from sulfoxides by infrared spectroscopy since they have a characteristic S=O band at about 1078 cm−1 compared to 1030–1060 cm−1 in sulfoxides. [15]

Formation and reactions

Synthetic thiosulfinates were first reported in 1947 by Cavallito and coworkers by oxidation of the corresponding disulfides. [16]

One example of a moderately stable thiosulfinate is the tert-butyl derivative, (CH3)3CS(O)SC(CH3)3. This thiosulfinate can be obtained in optical purity by catalytic asymmetric oxidation of di-tert-butyl disulfide with hydrogen peroxide. [17] Upon heating, (CH3)3CS(O)SC(CH3)3 decomposes into tert-butanethiosulfoxylic acid (CH3)3CSSOH) as shown by trapping studies. [18]

In a similar manner racemic methyl methanethiosulfinate (CH3S(O)SCH3) can be obtained by peracetic acid oxidation of dimethyl disulfide. [19] Methyl methanethiosulfinate decomposes thermally giving methanesulfenic acid (CH3SOH), the simplest sulfenic acid, as well as thioformaldehyde (CH2=S). Methyl methanethiosulfinate can also disproportionate to a 1:1 mixture of dimethyl disulfide and methyl methanethiosulfonate (CH3SO2SCH3) and rearrange via a Pummerer rearrangement to CH3S(O)CH2SSCH3. [20] [21]

An unusual three-membered ring thiosulfinate (a dithiirane 1-oxide) has been prepared through rearrangement of a 1,3-dithietane. [22] A related compound, 3-(9-triptycyl)dithiirane-1-oxide, was prepared by the reaction of (9-triptycyl)diazomethane and S8O . The X-ray structure of the dithiirane-1-oxide reveals a significantly lengthened sulfur-sulfur bond (211.9(3)pm). [23]

Thiosulfinates have also been invoked as intermediates in the oxidation of thiols to sulfonic acids.

Related Research Articles

<span class="mw-page-title-main">Ester</span> Compound derived from an acid

In chemistry, an ester is a compound derived from an acid in which the hydrogen atom (H) of at least one acidic hydroxyl group of that acid is replaced by an organyl group. These compounds contain a distinctive functional group. Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well. According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well, but not according to the IUPAC.

Sulfide (also sulphide in British English) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. Sulfide also refers to large families of inorganic and organic compounds, e.g. lead sulfide and dimethyl sulfide. Hydrogen sulfide (H2S) and bisulfide (HS) are the conjugate acids of sulfide.

<span class="mw-page-title-main">Allicin</span> Chemical compound

Allicin is an organosulfur compound obtained from garlic and leeks. When fresh garlic is chopped or crushed, the enzyme alliinase converts alliin into allicin, which is responsible for the aroma of fresh garlic. Allicin is unstable and quickly changes into a series of other sulfur-containing compounds such as diallyl disulfide. Allicin is an antifeedant, i.e. the defense mechanism against attacks by pests on the garlic plant.

<span class="mw-page-title-main">Dicarbonyl</span> Molecule containing two adjacent C=O groups

In organic chemistry, a dicarbonyl is a molecule containing two carbonyl groups. Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls are in close enough proximity that their reactivity is changed, such as 1,2-, 1,3-, and 1,4-dicarbonyls. Their properties often differ from those of monocarbonyls, and so they are usually considered functional groups of their own. These compounds can have symmetrical or unsymmetrical substituents on each carbonyl, and may also be functionally symmetrical or unsymmetrical.

<span class="mw-page-title-main">Protecting group</span> Group of atoms introduced into a compound to prevent subsequent reactions

A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis.

Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature is abound with organosulfur compounds—sulfur is vital for life. Of the 20 common amino acids, two are organosulfur compounds, and the antibiotics penicillin and sulfa drugs both contain sulfur. While sulfur-containing antibiotics save many lives, sulfur mustard is a deadly chemical warfare agent. Fossil fuels, coal, petroleum, and natural gas, which are derived from ancient organisms, necessarily contain organosulfur compounds, the removal of which is a major focus of oil refineries.

<span class="mw-page-title-main">Sulfoxide</span> Organic compound containing a sulfinyl group (>SO)

In organic chemistry, a sulfoxide, also called a sulphoxide, is an organosulfur compound containing a sulfinyl functional group attached to two carbon atoms. It is a polar functional group. Sulfoxides are oxidized derivatives of sulfides. Examples of important sulfoxides are alliin, a precursor to the compound that gives freshly crushed garlic its aroma, and dimethyl sulfoxide (DMSO), a common solvent.

Asparagusic acid is an organosulfur compound with the molecular formula C4H6O2S2 and systematically named 1,2-dithiolane-4-carboxylic acid. The molecule consists of a heterocyclic disulfide functional group (a 1,2-dithiolane) with a carboxylic acid side chain. It is found in asparagus and is believed to be the metabolic precursor to odorous sulfur compounds responsible for the distinctive smell of urine which has long been associated with eating asparagus.

<span class="mw-page-title-main">Sulfinic acid</span> Class of chemical compounds

Sulfinic acids are oxoacids of sulfur with the structure RSO(OH). In these organosulfur compounds, sulfur is pyramidal.

Pivalic acid is a carboxylic acid with a molecular formula of (CH3)3CCO2H. This colourless, odiferous organic compound is solid at room temperature. Two abbreviations for pivalic acid are t-BuC(O)OH and PivOH. The pivalyl or pivaloyl group is abbreviated t-BuC(O).

<span class="mw-page-title-main">Sulfenic acid</span> Organosulfur compound of the form R–SOH

In chemistry, a sulfenic acid is an organosulfur compound and oxoacid with the general formula R−S−OH. It is the first member of the family of organosulfur oxoacids, which also include sulfinic acids and sulfonic acids, respectively. The base member of the sulfenic acid series with R = H is hydrogen thioperoxide.

<i>syn</i>-Propanethial-<i>S</i>-oxide Chemical compound

syn-Propanethial S-oxide (or (Z)-propanethial S-oxide), a member of a class of organosulfur compounds known as thiocarbonyl S-oxides (formerly "sulfines"), is a volatile liquid that acts as a lachrymatory agent (triggers tearing and stinging on contact with the eyes).

<span class="mw-page-title-main">Alliinase</span> Class of enzyme

In enzymology, an alliin lyase is an enzyme that catalyzes the chemical reaction

An insertion reaction is a chemical reaction where one chemical entity interposes itself into an existing bond of typically a second chemical entity e.g.:

<span class="mw-page-title-main">Jones oxidation</span> Oxidation of alcohol

The Jones oxidation is an organic reaction for the oxidation of primary and secondary alcohols to carboxylic acids and ketones, respectively. It is named after its discoverer, Sir Ewart Jones. The reaction was an early method for the oxidation of alcohols. Its use has subsided because milder, more selective reagents have been developed, e.g. Collins reagent.

In organic chemistry, thiocarboxylic acids or carbothioic acids are organosulfur compounds related to carboxylic acids by replacement of one of the oxygen atoms with a sulfur atom. Two tautomers are possible: a thione form and a thiol form. These are sometimes also referred to as "carbothioic O-acid" and "carbothioic S-acid" respectively. Of these the thiol form is most common.

<span class="mw-page-title-main">Sulfinyl halide</span> Class of chemical compounds

Sulfinyl halide have the general formula R−S(O)−X, where X is a halogen. They are intermediate in oxidation level between sulfenyl halides, R−S−X, and sulfonyl halides, R−SO2−X. The best known examples are sulfinyl chlorides, thermolabile, moisture-sensitive compounds, which are useful intermediates for preparation of other sufinyl derivatives such as sulfinamides, sulfinates, sulfoxides, and thiosulfinates. Unlike the sulfur atom in sulfonyl halides and sulfenyl halides, the sulfur atom in sulfinyl halides is chiral, as shown for methanesulfinyl chloride.

<span class="mw-page-title-main">Sulfoxylic acid</span> Chemical compound

Sulfoxylic acid (H2SO2) (also known as hyposulfurous acid or sulfur dihydroxide) is an unstable oxoacid of sulfur in an intermediate oxidation state between hydrogen sulfide and dithionous acid. It consists of two hydroxy groups attached to a sulfur atom. Sulfoxylic acid contains sulfur in an oxidation state of +2. Sulfur monoxide (SO) can be considered as a theoretical anhydride for sulfoxylic acid, but it is not actually known to react with water.

Dihydroxydisulfane or hypodithionous acid is a reduced sulfur oxyacid with sulfur in a formal oxidation state of +1, but the valence of sulfur is 2. The structural formula is HO−S−S−OH, with all atoms arranged in a chain. It is an isomer of thiosulfurous acid but is lower in energy. Other isomers include HOS(=O)SH, HOS(=S)OH, and HS(=O)2SH. Disulfur monoxide, S2O, can be considered as the anhydride. Unlike many of these other reduced sulfur acids, dihydroxydisulfane can be formed in a pure state by reacting hydrogen sulfide with sulfur dioxide at −70 °C in dichlorodifluoromethane.

<span class="mw-page-title-main">Sulfine</span> Chemical compound

Sulfinylmethane or sulfine is an organic compound with molecular formula H2CSO. It is the simplest sulfine. Sulfines are chemical compounds with the general structure XY=SO. IUPAC considers the term 'sulfine' obsolete, preferring instead thiocarbonyl S-oxide; despite this, the use of the term sulfine still predominates in the chemical literature.

References

  1. See sulfoxide for discussion and references regarding the bonding in divalent monooxosulfur structures.
  2. Block, S. S.; Weidner, J. P. (1966) [1 Sept 1964]. "Vibrational behavior and structure of disulfide dioxides (thiolsulfonates)". Applied Spectroscopy. 20 (2): 73–79. Bibcode:1966ApSpe..20...73B. doi:10.1366/000370266774386272.
  3. Kice JL (1980). "Mechanisms and reactivity in reactions of organic oxyacids of sulfur and their anhydrides". Advances in Physical Organic Chemistry. 17: 65–181. doi:10.1016/S0065-3160(08)60128-8. ISBN   9780120335176.
  4. Takata, T; Endo, T (1990). "Thiosulphinic acids and esters". In S. Patai (ed.). The Chemistry of Sulphinic Acids, Esters and Their Derivatives. New York: John Wiley. pp. 527–575. doi:10.1002/9780470772270.ch18. ISBN   9780470772270.
  5. Braverman, S; Cherkinsky, M.; Levinger, S. (2007). "Alkanethiosulfinic Acid Esters". Sci. Synth. 39: 229–235.
  6. Kubec, R; Cody, RB; Dane, AJ; Musah, RA; Schraml, J; Vattekkatte, A; Block, E (2010). "Applications of DART Mass Spectrometry in Allium Chemistry. (Z)-Butanethial S-Oxide and 1-Butenyl Thiosulfinates and their S-(E)-1-Butenylcysteine S-Oxide Precursor from Allium siculum". J. Agric. Food Chem. 58 (2): 1121–1128. doi:10.1021/jf903733e. PMID   20047275.
  7. Block, E; Dane, AJ; Thomas, S; Cody, RB (2010). "Applications of Direct Analysis in Real Time–Mass Spectrometry (DART-MS) in Allium Chemistry. 2-Propenesulfenic and 2-Propenesulfinic Acids, Diallyl Trisulfane S-Oxide and Other Reactive Sulfur Compounds from Crushed Garlic and Other Alliums". J. Agric. Food Chem. 58 (8): 4617–4625. Bibcode:2010JAFC...58.4617B. doi:10.1021/jf1000106. PMID   20225897.
  8. Hirai, N; Sakashita, S; Sano, T; Inoue, T; Ohigashi, H; Premasthira, C; Asakawa, Y; Harada, J; Fujii, Y (2000). "Allelochemicals of the tropical weed Sphenoclea zeylanica". Phytochemistry. 55 (2): 131–140. Bibcode:2000PChem..55..131H. doi:10.1016/S0031-9422(00)00264-8. PMID   11065289.
  9. Kubec, R; Kim, S; Musah, RA (2002). "S-Substituted cysteine derivatives and thiosulfinate formation in Petiveria alliacea--Part II" (PDF). Phytochemistry. 61 (6): 675–680. Bibcode:2002PChem..61..675K. doi:10.1016/S0031-9422(02)00328-X. PMID   12423888.
  10. Yanagawa, H; Kato, T; Kitahara, Y (1973). "Asparagusic acid-S-oxides, new plant growth regulators in etiolated young asparagus shoots". Tetrahedron Letters. 14 (13): 1073–1075. doi:10.1016/S0040-4039(01)95907-6.
  11. Kato, A; Numata M (1972). "Brugierol and isobrugierol, trans- and cis-1,2-dithiolane-1-oxide, from Brugiera conjugata". Tetrahedron Letters. 13 (3): 203–206. doi:10.1016/S0040-4039(01)84280-5.
  12. Lynett, PT; Butts, K; Vaidya, V; Garretta, GE; Pratt, DA (2011). "The mechanism of radical-trapping antioxidant activity of plant-derived thiosulfinates". Org. Biomol. Chem. 9 (9): 3320–3330. doi:10.1039/c1ob05192j. PMID   21445384.
  13. Kim, S; Kubec, R; Musah, RA (2006). "Antibacterial and antifungal activity of sulfur-containing compounds from Petiveria alliacea" (PDF). Journal of Ethnopharmacology. 104 (1–2): 188–192. doi:10.1016/j.jep.2005.08.072. PMID   16229980.
  14. Block, E.; Cotelesage, J.J.H.; Dikarev, E.; Garosi, B.; George, G.N.; Musah, R.A.; Vogt, L.I.; Wei, Z.; Zhang, Y. (2024). "Re-examination of the claimed isolation of stable noncyclic 1,2-disulfoxides". Organic Letters. 26 (45): 9619–9624. doi: 10.1021/acs.orglett.4c02849 . PMC   11574841 . PMID   39230394.
  15. Block E (2010). Garlic and Other Alliums: The Lore and the Science. Royal Society of Chemistry. ISBN   978-0-85404-190-9.
  16. Small, LD; Bailey, JH; Cavallito, CJ (1947). "Alkyl thiolsulfinates". J. Am. Chem. Soc. 69 (7): 1710–1713. Bibcode:1947JAChS..69.1710S. doi:10.1021/ja01199a040. PMID   20251406.
  17. Weix, DJ; Ellman, JA (2005). "(RS)-(+)-2-Methyl-2-Propanesulfinamide [tert-Butanesulfinamide]". Organic Syntheses. 82: 157. doi:10.1002/0471264229.os082.24.
  18. Block, E (1972). "The Chemistry of Alkyl Thiosulfinate Esters. III. tert-Butanethiosulfoxylic Acid". J. Am. Chem. Soc. 94 (2): 644–645. Bibcode:1972JAChS..94..644B. doi:10.1021/ja00757a060.
  19. Moore, TL; O'Connor, DE (1966). "The Reaction of Methanesulfenyl Chloride with Alkoxides and Alcohols. Preparation of Aliphatic Sulfenate and Sulfinate Esters". J. Org. Chem. 31 (11): 3587–3592. doi:10.1021/jo01349a027.
  20. Block, E; O'Connor, J (1974). "The Chemistry of Alkyl Thiosulfinate Esters. VI. Preparation and Spectral Studies". J. Am. Chem. Soc. 96 (12): 3921–3929. Bibcode:1974JAChS..96.3921B. doi:10.1021/ja00819a033.
  21. Block, E; O'Connor, J (1974). "The Chemistry of Alkyl Thiosulfinate Esters. VII. Mechanistic Studies and Synthetic Applications". J. Am. Chem. Soc. 96 (12): 3929–3944. Bibcode:1974JAChS..96.3929B. doi:10.1021/ja00819a034.
  22. Ishii, A; Akazawa, T; Ding, MX; Honjo, T; Nakayama, J; Hoshino, M; Shiro, M (1993). "First isolable dithiiranes: 3-(1,1,3,3-tetramethyl-4-oxo-4-phenylbutyl)-3-phenyldithiirane 1-oxides". J. Am. Chem. Soc. 115 (11): 4914–4915. Bibcode:1993JAChS.115.4914I. doi:10.1021/ja00064a072.
  23. Ishii, A; Kawai, T; Noji, M; Nakayama, J (2005). "Synthesis and reactions of a monosubstituted dithiirane 1-oxide, 3-(9-triptycyl)dithiirane 1-oxide". Tetrahedron. 61 (28): 6693–6699. doi:10.1016/j.tet.2005.05.017.