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Terminal olefins to chromans, isochromans, and pyrans via allylic C-H oxidation.

ABSTRACT: The synthesis of chroman, isochroman, and pyran motifs has been accomplished via a combination of Pd(II)/bis-sulfoxide C-H activation and Lewis acid co-catalysis. A wide range of alcohols are found to be competent nucleophiles for the transformation under uniform conditions (catalyst, solvent, temperature). Mechanistic studies suggest that the reaction proceeds via initial C-H activation followed by a novel inner-sphere functionalization pathway. Consistent with this, the reaction shows reactivity trends orthogonal to those of traditional Pd(0)-catalyzed allylic substitutions.

SUBMITTER: Ammann SE

PROVIDER: S-EPMC4132955 | biostudies-literature |

REPOSITORIES: biostudies-literature

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