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Short Enantioselective Total Synthesis of Tatanan?A and 3-epi-Tatanan?A Using Assembly-Line Synthesis.

ABSTRACT: Short and highly stereoselective total syntheses of the sesquilignan natural product tatanan A and its C3 epimer are described. An assembly-line synthesis approach, using iterative lithiation-borylation reactions, was applied to install the three contiguous stereocenters with high enantio- and diastereoselectivity. One of the stereocenters was installed using a configurationally labile lithiated primary benzyl benzoate, resulting in high levels of substrate-controlled (undesired) diastereoselectivity. However, reversal of selectivity was achieved by using a novel diastereoselective Matteson homologation. Stereospecific alkynylation of a hindered secondary benzylic boronic ester enabled completion of the synthesis in a total of eight steps.

SUBMITTER: Noble A

PROVIDER: S-EPMC5215435 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Short Enantioselective Total Synthesis of Tatanan A and 3-epi-Tatanan A Using Assembly-Line Synthesis.

Noble Adam A Roesner Stefan S Aggarwal Varinder K VK

Angewandte Chemie (International ed. in English) 20161116 51

Short and highly stereoselective total syntheses of the sesquilignan natural product tatanan A and its C3 epimer are described. An assembly-line synthesis approach, using iterative lithiation-borylation reactions, was applied to install the three contiguous stereocenters with high enantio- and diastereoselectivity. One of the stereocenters was installed using a configurationally labile lithiated primary benzyl benzoate, resulting in high levels of substrate-controlled (undesired) diastereoselect ...[more]

PMID: 27865037

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