Sharpless palladium catalyzed

Several enantioselective approaches to vitamin E (1), based on resolution of the products, the use of enantiopure natural building blocks, auxiliary controlled reactions and asymmetric oxidations have been described. In addition, a palladium-catalyzed asymmetric allylic alkylation reaction to build up the chiral chroman framework has been employed by Trost. Tietze and coworkers have developed asymmetric syntheses of the chiral chroman moiety using either the selective ally-lation of an alkyl methyl ketone or a Sharpless dihydroxylation as the key step. However, none of these methods is efficient enough for an industrial approach. ... 

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