Diol monotosylates, bicyclic

Monocyclic ethyleneketones from bicyclic diol monotosylates s. 19, 937... 

The stereocontrolled synthesis of 5 -substituted kainic acids was achieved by A. Rubio et a. The C3 and C4 substituents were introduced by the Wharton fragmentation of a bicyclic monotosylated 1,3-diol. When this secondary alcohol was exposed to KOf-Bu, the corresponding fragmentation product was obtained in moderate yield. Jones oxidation of the aldehyde to the carboxylic acid followed by hydrolysis of the ester and removal of the Boc group resulted in the desired substituted kainic acid. 

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