Oxidation-Wittig reactions, manganese dioxide

Miscellaneous Reactions. So-called Oxidation-Wittig conditions , where a primary alcohol is oxidised using manganese dioxide in the presence of a stabilised ylide, have been applied for the first time to unactivated alcohols, producing a, 3-unsaturated esters in high yields (Scheme 18). Fluorenyl-... 

Farnesol may be also converted into ( , )-homofarnesol by the following sequence oxidation with manganese dioxide, a Wittig reaction, and hydrobora-tion using disiamylborane, which is prepared in situ from the borane-TH F complex and 2-methylbut-2-ene. The overall yield is 70 %. [248]... 

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