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Prins fluorination cyclisations: Preparation of 4-fluoro-pyran and -piperidine heterocycles.

ABSTRACT: The Prins reaction was investigated using BF?.OEt? as a Lewis acid. It has been recently demonstrated, that if BF?.OEt? is used in stoichiometric amounts then these reactions generate fluorinated products where the BF?.OEt? contributes fluoride ion to quench the intermediate carbocations. In this study oxa- and aza-Prins reactions for the synthesis of 4-fluoro-pyrans and -piperidines were investigated. The products were obtained in good yields, but only with moderate diastereoselectivity. These Prins fluorination reactions can be accelerated under microwave conditions. The study extends the Prins fluorination methodology for the generation of the C-F bond in heterocycles.

SUBMITTER: Launay GG

PROVIDER: S-EPMC2874316 | biostudies-other | 2010

REPOSITORIES: biostudies-other

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Prins fluorination cyclisations: Preparation of 4-fluoro-pyran and -piperidine heterocycles.

Launay Guillaume G GG Slawin Alexandra M Z AM O'Hagan David D

Beilstein journal of organic chemistry 20100426

The Prins reaction was investigated using BF₃.OEt₂ as a Lewis acid. It has been recently demonstrated, that if BF₃.OEt₂ is used in stoichiometric amounts then these reactions generate fluorinated products where the BF₃.OEt₂ contributes fluoride ion to quench the intermediate carbocations. In this study oxa- and aza-Prins reactions for the synthesis of 4-fluoro-pyrans and -piperidines were investigated. The products were obtained in good yields, but only with moderate diastereoselectivity. These ...[more]

PMID: 20502655

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