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Formal synthesis of (-)-neopeltolide featuring a highly stereoselective oxocarbenium formation/reduction sequence. | LitMetric

The formal synthesis of the unnatural (-)-neopeltolide core is discussed in detail. Efficient application of the Evans' protocol for the synthesis of 1,3-syn-diols via an intramolecular hetero-Michael addition followed by reductive deprotection of the resulting benzylidene acetal allowed for swift access to the delta-lactone. Central to the synthetic approach is a tandem nucleophilic addition-diastereoselective axial reduction of an in situ generated oxocarbenium cation to assemble the beta-C-glycoside moiety of the neopeltolide core.

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Source
http://dx.doi.org/10.1021/jo100443hDOI Listing

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