Alkanesulfonic acid catalyst

Whereas superaeid (HF/BF3, HF/SbF, HF/TaF FS03FI/SbF3, etc.)-eatalyzed hydroearbon transformations were first explored in the liquid phase, subsequently, solid aeid eatalyst systems, sueh as those based on Nafion-H, longer-chain perfluorinated alkanesulfonic acids, fluorinated graphite intercalates, etc. were also developed and utilized for heterogeneous reactions. The strong acidic nature of zeolite catalysts was also successfully explored in cases such as FI-ZSM-5 at high temperatures. 

Fluorinated and Ghlorfluorinated Sulfonic Acids. The synthesis of chlorinated and fluorinated sulfonic acids has been extensively reviewed (91,92). The Hterature discusses the reaction of dialkyl sulfides and disulfides, sulfoxides and sulfones, alkanesulfonyl haHdes, alkanesulfonic acids and alkanethiols with oxygen, hydrogen chloride, hydrogen fluoride, and oxygen—chloride—hydrogen fluoride mixtures over metal haHde catalysts, such as... 

The acid catalysts include sulfuric acid, phosphoric acid, hydrogen fluoride, dihydroxyfluorboric acid, and alkanesulfonic acids. Some heavy metal sulfates, phosphates, sulfides and other salts are also catalysts it seems probable that they undergo partial reduction to acidic compounds during the polymerization reactions. 

MSA and other lower alkanesulfonic acids are useful for plating of lead, nickel, cadmium, silver, and zinc (409). MSA also finds use in plating of tin, copper, lead, and other metals. It is also used in printed circuit board manufacture. In metal finishing the metal coating can be stripped chemically or electrolytically with MSA. MSA also finds use in polymers and as a polymer solvent and as a catalyst for polymerization of monomers such as acrylonitrile. MSA also finds use in ion-exchange resin regeneration because of the high solubility of many metal salts in aqueous solutions. 

The first catalytic sulfoxidation of saturated hydrocarbons with S02/02 by vanadium catalysts to give alkanesulfonic acids has been reported.302 The best results were achieved with VO(acac)2 ... 

Jones and co-workers976 have recently reported the use of catalyst 49 (Figure 5.15) with perfluorinated alkanesulfonic acid sites anchored to SBA-15 as a methylaluminoxane-free supported cocatalyst for ethylene polymerization. When catalyst 49 and trimethylaluminum were used in combination with Cp 2ZrMe2 as the metallocene precatalyst, productivities as high as 1000 kg polyethylene molZr-1 h 1 were obtained without experiencing reactor fouling. 

Alkanesulfonic acids can be prepared from the thiols or disulfides and air using cocatalytic DMSO and HBr.f The use of aqueous DMSO in the absence of air, but in the presence of a halogen or hydrogen halide catalyst, readily converts most aliphatic, aromatic, and heterocyclic thiols or disulfides to the corresponding sulfonic acid. In effect, DMSO oxidizes the hydrohalide to the molecular halogen, which then reacts with the organosulfur substrates. Water serves as a proton and oxygen source, and inhibits the Pummerer-type decomposition of the DMSO. 

Other oxidants for the conversion of alkanethiols and disulfide alkanesulfonic acids have been described. H2O2, in combination with catalysts, e.g., peroxycar-bonates, alkanesulfonic acids, molybdates, tungstates, or HCl, was effective in producing alkanesulfonic acids.At lower temperatures (25-35°C) the combination of H2O2 catalytic HCl afforded the alkanesulfonyl chlorides. Kinetic studies of the photooxidation with O2 in acetonitrile and other solvents have been reported and the relative stabilities of the various... 

Alkanedisulfonic acids are prepared by heating an alkanesulfonic acid with chlorosulfonic acid at 70-160 °C in the presence of air (oxygen), optionally over an activated charcoal catalyst. Methanesulfonic acid reacted with chlorosulfonic acid at 100 °C (1 hour) to give a mixture containing methanedisulfonic acid (34%). (For further details see Chapter 9 p 267.)... 

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