C-F sp2 bond functionalization mediated by niobium complexesElectronic supplementary information (ESI) available. CCDC 1403876 and 1403877. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5dt02082d

Insertion chemistry of isocyanide molecules was used to functionalize C-F sp 2 bonds after their oxidative addition across the metal center in a β-diketiminate niobium( iii ) imido complex (BDI)Nb(N t Bu)(C 6 H 6 ). The complexes formed, 3a-b ([BDI]Nb(PhC&z.dbd;N)(N t Bu)(F) (R = 1,6-diisopropylphenyl, tert -butyl), were characterized by NMR spectroscopy and X-ray analysis. Further treatment with phenylsilane induced H/F exchange under mild conditions, which was followed by hydride transfer to the inserted isocyanide. Divergent reactivity was observed when the two analogous aryl and tert -butyl isocyanide insertion products were treated with phenylsilane. The functionalization of fluorobenzene is described via insertion of isocyanide after the oxidative addition of the C-F bond.