Alkene cleavage to carboxylic acids

This is one of the commonest reactions of RuO and perhaps its current major application. Examples of such reactions are given in Table 3.4. As mentioned 

An early example is cleavage of an alkene linkage with RnO (Fig. 3.18) in the conversion of a diketo diphenyl ethylene to a nor-diketo acid by RnOyaq. Na(IO )/ acetone concomitant destruction of the phenyl rings also occnrs [206]. 

Oxidation of diethyl 2-aUyl-2-hydroxypentanedioate by RnCyaq. Na(IO )/ CHjCN-EtOAc gave triethyl homocitrate and the corresponding lactone [209]. Oxidation of cyclopentene to glutaric acid by RnCyaq. Na(C10)/CCl or CH Cl showed that addition of CHjCN and also NaOH greatly improved yields [210]. Perfluoro alkenes were cleaved by Ru02/IO(OH)j, Na(ClO) or CH COOOH/water-Freon 113 to carboxylic acids CO was also formed or, in the case of perfluoropro-pene, pefluoroacetic acid and COF (Table 3.6) [211]. 

2-en-l-one, while ( )-5-allenyl-2, 5-dichloro-3-diethylamino-4,4-dimethoxy-cyclo-penten-4-en-l-one yielded 5-(lZ-carboxymethylene)-2-chloro-3-diethylamino-4, 4-dimethoxycyclopent-2-en-1 -one [212]. 

The trifluoroactate group can protect aromatic rings against oxidation by RuO generated from RuO /aq. Na(IO )/CCl. Thus isoeugenyl trifluoroacetate gave vanillin and vanillic acid (Table 3.6) [213]. Oxidation of various substituted 

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