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Indium-mediated allylation of aldehydes, ketones and sulfonimines with 2-(alkoxy)allyl bromides.

ABSTRACT: 2-(Alkoxy)propenyl bromides are readily prepared from 1,3-dibromo-2-propanol in a two-step sequence involving hydroxyl protection and sodium hydride-induced dehydrobromination. Indium-mediated allylation of aldehydes, ketones, and sulfonimines with 2-(alkoxy)propenyl bromides furnishes the corresponding homoallylic alcohols and sulfonamines in good yields. The products can be easily transformed into ?-hydroxy ketones and esters, as well as substituted dihydropyrans and protected ?-amino acids. Chiral 2-(alkoxy)propenyl halides, derived from (-)-menthol and D-glucal, furnish diastereomerically enriched products.

SUBMITTER: Dhanjee H

PROVIDER: S-EPMC2976063 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Indium-mediated allylation of aldehydes, ketones and sulfonimines with 2-(alkoxy)allyl bromides.

Dhanjee Heemal H Minehan Thomas G TG

Tetrahedron letters 20101001 42

2-(Alkoxy)propenyl bromides are readily prepared from 1,3-dibromo-2-propanol in a two-step sequence involving hydroxyl protection and sodium hydride-induced dehydrobromination. Indium-mediated allylation of aldehydes, ketones, and sulfonimines with 2-(alkoxy)propenyl bromides furnishes the corresponding homoallylic alcohols and sulfonamines in good yields. The products can be easily transformed into β-hydroxy ketones and esters, as well as substituted dihydropyrans and protected β-amino acids. C ...[more]

PMID: 21076649

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