Stereospecific Electrophilic Fluorination of Alkylcarbastannatrane Reagents
Xinghua Ma1,2, Mohamed Diane1, Glenn Ralph1,2
1Department of Chemistry, The City College of New York (CCNY), 160 Convent Avenue, New York, NY, 10031, USA.
Abstract:
We report the use of isolable primary and secondary alkylcarbastannatrane nucleophiles in site-specific fluorination reactions. These reactions occur without the need for transition metal catalysis or in situ activation of the nucleophile. In the absence of the carbastannatrane backbone, alkyltin nucleophiles exhibit no activity towards fluorination. When enantioenriched alkylcarbastannatranes are employed, fluorination occurs predominately via a stereoinvertive mechanism to generate highly enantioenriched alkyl fluoride compounds. These conditions can also be extended to stereospecific chlorination, bromination, and iodination reactions.
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