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Synthesis of chiral cyclohexanes and carbasugars by 6-exo-dig radical cyclisation reactions.

ABSTRACT: Treatment of 5-(tert-butyldimethylsilyl)-2,3-O-isopropylidene-D-ribose with lithium acetylides gave mixtures of syn- and anti-alkynols 2a-2c which were separated following protection as methoxymethyl ethers. These were converted to the corresponding iodides which underwent 6-exo-dig radical cyclisation to afford chiral cyclohexanes and carbasugars. Oxidation of the primary alcohols 6a-b gave the corresponding aldehydes which on treatment with Grignard reagents afforded a mixture of alcohols. The corresponding iodides underwent similar 6-exo-dig cyclisation to give fully functionalised cyclohexanes.

SUBMITTER: Shrivastava RK

PROVIDER: S-EPMC2605619 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

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Synthesis of chiral cyclohexanes and carbasugars by 6-exo-dig radical cyclisation reactions.

Shrivastava Rajeev K RK Maudru Elise E Singh Gurdial G Wightman Richard H RH Morgan Keith M KM

Beilstein journal of organic chemistry 20081119

Treatment of 5-(tert-butyldimethylsilyl)-2,3-O-isopropylidene-D-ribose with lithium acetylides gave mixtures of syn- and anti-alkynols 2a-2c which were separated following protection as methoxymethyl ethers. These were converted to the corresponding iodides which underwent 6-exo-dig radical cyclisation to afford chiral cyclohexanes and carbasugars. Oxidation of the primary alcohols 6a-b gave the corresponding aldehydes which on treatment with Grignard reagents afforded a mixture of alcohols. The ...[more]

PMID: 19104673

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