·
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Scheme 4 |
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Scheme 5 |
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Scheme 6 |
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Scheme 7 |
In the latter case, the resultant diols undergo oxidative cleavage to give aldehydes or ketones. This reaction is known as Lemieux-Johnson Oxidation. NaIO4 oxidizes the reduced osmium(VI) to osmium(VIII) along with the oxidative cleavage of the diols.