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Organocatalytic Asymmetric Synthesis of ?-Oxetanyl and ?-Azetidinyl Tertiary Alkyl Fluorides and Chlorides.

ABSTRACT: Asymmetric thiourea and squaramide catalysis provides access to synthetically versatile ?-oxetanyl and ?-azetidinyl alkyl halides exhibiting a tetrasubstituted chiral carbon center with high yields and enantioselectivities. The products are readily transformed with negligible erosion of enantiopurity and excellent diastereoselectivity to a diverse group of multifunctional compounds including fluorooxindoles with two contiguous chirality centers, fluorinated heterocyclic spiranes, and polyspiro compounds.

SUBMITTER: Ding R

PROVIDER: S-EPMC5937693 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Organocatalytic Asymmetric Synthesis of α-Oxetanyl and α-Azetidinyl Tertiary Alkyl Fluorides and Chlorides.

Ding Ransheng R Wolf Christian C

Organic letters 20180123 3

Asymmetric thiourea and squaramide catalysis provides access to synthetically versatile α-oxetanyl and α-azetidinyl alkyl halides exhibiting a tetrasubstituted chiral carbon center with high yields and enantioselectivities. The products are readily transformed with negligible erosion of enantiopurity and excellent diastereoselectivity to a diverse group of multifunctional compounds including fluorooxindoles with two contiguous chirality centers, fluorinated heterocyclic spiranes, and polyspiro c ...[more]

PMID: 29360370

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