Butane-2,3-Diol, Oxidation Periodate

Fig. 3. Recording of the limiting current at selected time-interval Oxidation of erj/iftro-butane-2,3-diol by periodate. [Decrease of periodic acid concentration with time followed continuously up to 4 min, then during the time intervals indicated. IM Acetate buffer of pH 5-6, 5 x 10 4m-KIO4, 5 X 10 m 6ry ftro-butane-2,3-diol. Current recorded at 25° at — 0-6 V (mercurous sulphate reference electrode). Figures on the abscissae give the time in minutes. The galvanometer zero and the current before the addition of periodate and after addition at t = 0 are marked. Full scale sensitivity 0-8 fiA.J (Redrawn not accurate to scale.)...

Lead tetraacetate (abbreviated LTA) reacts with diols to give the same kind of oxidative cleavage. When 69 is treated with LTA, the initial cyclic product is cyclic intermediate 73, which fragments to butanal and acetaldehyde. Periodic acid gives the same cleavage reaction. Both periodic acid and lead tetraacetate are mild and effective reagents for the oxidative cleavage of diols. 

Applications of POMs to catalysis have been periodically reviewed [33 0]. Several industrial processes were developed and commercialized, mainly in Japan. Examples include liquid-phase hydration ofpropene to isopropanol in 1972, vapor-phase oxidation of methacrolein to methacrylic acid in 1982, liquid-phase hydration of isobutene for its separation from butane-butene fractions in 1984, biphasic polymerization of THE to polymeric diol in 1985 and hydration of -butene to 2-butanol in 1989. In 1997 direct oxidation of ethylene to acetic acid was industrialized by Showa Denko and in 2001 production of ethyl acetate by BP Amoco. 

The overall rate of oxidation of 2-methyl-butane-2,3-diol at pH 4.5 (acetate buffer) and 0 °C exhibits complex kinetics which can be analysed in terms of the diester being formed at a rate comparable with its rate of breakdown to the products (Buist and Bunton ). The periodate species responsible for attacking 1,2-diols are probably IO4, and, in acid solution, HjIOs (Buist et Tracer... 

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