22223-61-6Relevant academic research and scientific papers
Reactivity of sulfur nucleophiles towards S-nitrosothiols
Munro, Andrew P.,Williams, D. Lyn H.
, p. 1794 - 1797 (2007/10/03)
Rate constants have been measured for the reactions of a range of S-nitrosothiols with the following sulfur-centred nucleophiles: sulfite ion, thiourea, thiocyanate ion, thiosulfate ion, thiomethoxide ion and sulfide ion. Many of the reactions were very fast and were followed in a stopped-flow spectrophotometer. For the sulfite reaction the reactive species over the pH range 4-8 was shown to be exclusively SO32-. For two RSNO species the reactivity sequence was established as: SO32- > MeS- > S2O32- ? SC(NH2)2 SCN-. The reaction with sulfide ion was also rapid and generated a fairly stable yellow species (λmax 410 nm), which was probably the nitrosodisulfide ion ONSS-, but the absorbance-time data were too complex for a simple kinetic analysis. This reaction could have some potential as an analytical procedure for the determination of RSNO species. The kinetic results are discussed in terms of the factors affecting nucleophilicity and are compared with the corresponding reactions of other nitrosating species.
Oxidation of Sulfur Compounds. II. Thermal Reactions of NO2 with Aliphatic Sulfur Compounds
Balla, R. Jeffrey,Heicklen, Julian
, p. 6314 - 6317 (2007/10/02)
The reactions of NO2 with (CH3)2S, (CH3S)2, CH3SNO, and CH3SH were studied at 23 deg C in a Pyrex cell with a pinhole bleed to a mass spectrometer.In all cases reaction proceeded readily and NO was evolved.The (CH3)2S-NO2 reaction also produced (CH3)2SO.The CH3SH-NO2 reaction gave CH3SNO and (CH3S)2 as initial products, which in turn were further oxidized.The CH3SNO-NO2 reaction gave (CH3S)2 and (CH3SO)2, presumably with CH3S(O)NO formed as an undetected unstable intermediate.The (CH3S)2-NO2 reaction gave (CH3SO)2 as a primary product which further oxidized, presumably to give (CH3SO2)2.Undoubtedly (CH3S)2O and (CH3SO)2O were undetected intermediates leading to the formation of (CH3SO)2 and (CH3SO2)2, respectively.The indicated initial reactions are (CH3)2S + NO2 -> (CH3)2SO + NO (1), (CH3S)2 + NO2 -> (CH3S)2O + NO (3), CH3SNO + NO2 -> CH3S(O)NO + NO (7), CH3SH + NO2 -> CH3SNO + HO (12a).In addition another reaction may also occur: CH3SH + NO2 -> CH3S(O)H + NO (12c).The only reaction slow enough to measure was reaction 1 and it has a rate coefficient k1 ca. 9*10-21 cm3/s.The (CH3S)2O is further oxidized by NO2 in a sequence of reactions to give first (CH3SO)2 and subsequently (CH3SO2)2.The CH3S(O)NO is thermally unstable and decomposes to give CH3SO radicals and NO.The CH3SO species appears to react via CH3SO + CH3SNO -> (CH3S)2 + NO2 (9), 2CH3SO -> (CH3SO)2 (10) or possibly by CH3SO + CH3SNO -> (CH3S)2O + NO (11).
Oxidation of sulfur compounds. I. The photolysis of CH3SH and (CH3S)2 in the presence of NO
Balla, R. Jeffrey,Heicklen, Julian
, p. 162 - 170 (2007/10/02)
Both CH3SH and (CH3S)2, as well as their mixtures, were photolyzed in the presence of NO at 23 +/-1 deg C.The photolyses were carried out in a 631 mL quartz vessel with a pinhole bleed to a quadrupole mass spectrometer for continual analysis of products.After the termination of exposure, further product analysis was made by gas chromatography.The identified products of reaction were CH3SNO, (CH3S)2, H2, and N2.Hydrogen atoms, formed from the photolysis of CH3SH, reacted with both NO and CH3SH: H + NO + M --> HNO + M H + CH3SH --> H2 +CH3S with k5/k4 = 626 +/- 42 Torr for NO as a chaperone.The CH3S radical adds to NO CH3S + NO CH3SNO CH3SNO + M --> CH3SNO + M with k-2a/k-2b = 83 +/- 52 Torr.As the CH3SNO accumulates, CH3S also reacts with CH3SNO CH3S + CH3SNO --> (CH3S)2 + NO with k6/k2a = 0.84 +/-0.27.At high NO pressures a chain process occurs which is attributed to: H + NO --> adduct H + ξCH3S where ξ is probably 4.0.Termination is most easily represented by HNO --> termination with k8/k7 = 85.0 +/-7.8 Torr
Reactions of OH Radicals with Methanethiol, Dimethyl Sulfide, and Dimethyl Disulfide in Air
Hatakeyama, Shiro,Akimoto, Hajime
, p. 2387 - 2395 (2007/10/02)
Photooxidations of CH3SH, CH3SSCH3 (DMDS), and CH3SCH3 (DMS) in air were performed with alkyl nitrites as sources of OH radicals.Sulfur-containing final products are SO2, CH3SO3H (methanesulfonic acid), and a little H2SO4 in all cases.CH3SH reacts with OH to form an adduct, which further reacts with alkyl nitrites to give CH3SNO (methyl thionitrite) and the corresponding alcohols.CH3S radical produced by photolysis of CH3SNO gives final products.DMDS also reacts with OH via addition followed by rapid cleavage of the S-S bond, resulting in CH3S and CH3SOH.Reaction of DMS with OH can be explained by both addition and abstraction.In both cases the CH3S radical is the main intermediate which produces final products.The reaction of the CH3S radical with O2 proceeds via addition and gives HCHO + SO2 or CH3SO3H as final products.The rate constant ratios of CH3S with NO and O2 were obtained to be ca. 2 x 1E3, which is about one-tenth of that for CH3O.
