Chemoselective, Substrate-directed Fluorination of Functionalized Cyclopentane β-Amino Acids
Loránd Kiss1, Melinda Nonn2, Reijo Sillanpää3
1Institute of Pharmaceutical Chemistry, University of Szeged, 6720, Szeged, Eötvös u. 6, Hungary.
Abstract:
This work describes a substrate-directed fluorination of some highly functionalized cyclopentane derivatives. The cyclic products incorporating CH2 F or CHF2 moieties in their structure have been synthesized from diexo- or diendo-norbornene β-amino acids following a stereocontrolled strategy. The synthetic study was based on an oxidative transformation of the ring carbon-carbon double bond of the norbornene β-amino acids, followed by transformation of the resulted "all cis" and "trans" diformyl intermediates by fluorination with "chemodifferentiation".
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