Enantioselective, Catalytic Fluorolactonization Reactions with a Nucleophilic Fluoride Source
Eric M Woerly1, Steven M Banik1, Eric N Jacobsen1
1Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States.
Abstract:
The enantioselective synthesis of 4-fluoroisochromanones via chiral aryl iodide-catalyzed fluorolactonization is reported. This methodology uses HF-pyridine as a nucleophilic fluoride source with a peracid stoichiometric oxidant and provides access to lactones containing fluorine-bearing stereogenic centers in high enantio- and diastereoselectivity. The regioselectivity observed in these lactonization reactions is complementary to that obtained with established asymmetric electrophilic fluorination protocols.
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