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General Methodologies Toward cis-Fused Quinone Sesquiterpenoids. Enantiospecific Synthesis of the epi-Ilimaquinone Core Featuring Sc-Catalyzed Ring Expansion.

ABSTRACT: A stereocontrolled approach to the cis-decalin framework of clerodane diterpenes and biologically active quinone sesquiterpenes is reported. Starting from an inexpensive optically pure tetrahydroindanone, Birch reductive alkylation builds two new contiguous chiral centers-one of which is quaternary and all-carbon-substituted. Also featured is a highly regioselective diazoalkane-carbonyl homologation reaction to prepare the 6,6-bicyclic skeleton. Therein, the utility of Sc(OTf)? as a mild catalyst for formal 1C insertion in complex settings is demonstrated.

SUBMITTER: Kaplan HZ

PROVIDER: S-EPMC6152358 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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General Methodologies Toward cis-Fused Quinone Sesquiterpenoids. Enantiospecific Synthesis of the epi-Ilimaquinone Core Featuring Sc-Catalyzed Ring Expansion.

Kaplan Hilan Z HZ Rendina Victor L VL Kingsbury Jason S JS

Molecules (Basel, Switzerland) 20170624 7

A stereocontrolled approach to the cis-decalin framework of clerodane diterpenes and biologically active quinone sesquiterpenes is reported. Starting from an inexpensive optically pure tetrahydroindanone, Birch reductive alkylation builds two new contiguous chiral centers-one of which is quaternary and all-carbon-substituted. Also featured is a highly regioselective diazoalkane-carbonyl homologation reaction to prepare the 6,6-bicyclic skeleton. Therein, the utility of Sc(OTf)₃ as a mild ...[more]

PMID: 28672821

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