Selective C-F Bond Allylation of Trifluoromethylalkenes
Chuan Zhu1, Meng-Meng Sun1, Kai Chen1
1Technical Institute of Fluorochemistry (TIF), Institute of Advanced Synthesis (IAS), School of Chemistry and Molecular Engineering, Nanjing Tech University, 30 South Puzhu Road, Nanjing, 211816, P. R. China.
Abstract:
Selective C-F bond functionalization of CF3 group represents an appealing strategy for the incorporation of pharmaceutically privileged difluoromethylene moiety. Despite the recent significant advancement attained in the functionalization of Ar-CF3 molecules, prescriptions amenable for alkenyl-CF3 congeners remain sufficiently inadequate. Herein, we report a strategically novel protocol for the C-F bond elaboration of trifluoromethylalkene derivatives. By using readily available allyl metallics as nucleophilic coupling partner, the present reaction enables an expedient construction of structurally diversified CF2 -bridged 1,5-dienes. Furthermore, the exquisite selectivity observed in this transformation is revealed to be based on the underlying mechanism that consists of a cascade of nucleophilic SN 2' defluorinative allylation and electronically promoted Cope rearrangement.
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