6922-46-9Relevant articles and documents
ALKANEPERSULFONIC ACID-SO2 SYSTEM AS A NEW SULFONATING REAGENT
Safiullin, R. L.,Zaripov, R. N.,Khalilov, L. M.,Komissarov, V. D.
, p. 1991 (1990)
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Visible-light-induced sulfoxidation of alkanes in the presence of titania
Parrino, Francesco,Ramakrishnan, Ayyappan,Damm, Cornelia,Kisch, Horst
, p. 713 - 720 (2013/01/14)
The first catalytic photosulfoxidation of alkanes is accomplished in the presence of titanium dioxide and visible light (λ≥400 nm) under an atmosphere of SO2/O2. For n-heptane and cyclohexane the reaction is performed in the neat liquid, for adamantane in glacial acetic acid. Charge-transfer (CT) complexation of sulfur dioxide by the titania surface generates a CT band at 400-420 nm responsible for the visible-light activity of otherwise only UV light absorbing titania. The primary charges generated upon optical electron transfer produce alkyl radicals by dissociative electron transfer from the alkane and by hydrogen abstraction by OH radicals produced from oxygen reduction. Once formed, the alkyl radicals initiate a radical chain reaction as known from the classical UV-induced sulfoxidation in the absence of a catalyst. The reaction exhibits features characteristic for product inhibition by strong adsorption. Accordingly, the initial photocatalytic activity is fully restored after washing the catalyst with methanol. Time-resolved photovoltage measurements indicate that photocatalyst deactivation is connected with a change from n-type to p-type titanium dioxide. Small amounts of water and radical scavengers inhibit product formation. The reaction proceeds with high chemoselectivity because only traces of expected by-products like sulfates, ketones, and alcohols are formed. Thus, in addition to its basic role in visible-light-induced charge generation, the surface of titania enables also a chemoselective C-S bond formation.
Semiconductor-photocatalyzed sulfoxidation of alkanes
Parrino, Francesco,Ramakrishnan, Ayyappan,Kisch, Horst
experimental part, p. 7107 - 7109 (2009/04/07)
(Equation Presented) The C-H activation of alkanes with visible light is possible with a semiconductor as the photocatalyst. Upon irradiation, a mixture of titanium dioxide, sulfur dioxide, and oxygen can be used to convert alkanes into the corresponding sulfonic acids (see scheme).
Process for preparing organic sulfur acids or salts thereof
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, (2008/06/13)
A process for producing organic sulfur acid or a salt thereof of the present invention allows an organic substrate to react with a sulfur oxide in the presence of a metallic compound catalyst and in the absence of N-hydroxy and N-oxo cyclic imide compounds and thereby yields a corresponding organic sulfur acid or a salt thereof. Such organic substrates include, for example, (a) homocyclic or heterocyclic compounds having a methylene group, (b) compounds having a methine carbon atom, (c) compounds having a methyl group or methylene group at the adjacent position to an unsaturated bond, (d) non-aromatic heterocyclic compounds having a carbon-hydrogen bond at the adjacent position to a hetero atom, and (e) straight-chain alkanes. The sulfur oxide includes, for example, sulfur dioxide. This production process can efficiently produce an organic sulfur acid or a salt thereof under mild conditions.
