title: Synthesis and reactivity of fluorenyl-tethered N-heterocyclic stannylenes.
abstract: A fluorenyl (Fl) tethered diamine was synthesised by nucleophilic substitution of (bromoethyl)fluorene with a diisopropylphenyl (Dipp) substituted diamine to give FlC2H4N(H)C2H4N(H)Dipp (1a) in good yield (85%). Lithiation of 1a with n-BuLi proceeded with coordination of the Li cation to the aromatic fluorenide ring (2), and with subsequent equivalents of n-BuLi, the secondary amines were then sequentially deprotonated. A fluorenyl-tethered N-heterocyclic stannylene (NHSn) was synthesised from the reaction of 1a with SnN''2 {N'' = N(SiMe3)2} as a neutral dimeric species (5), and this was deprotonated with LiN'' to give the corresponding dianionic fluorenide-tethered NHSn (6). Reactions of [{Rh(cod)(μ-Cl)}2] with the mono-deprotonated ligand 2 led to the formation of a mixed-donor amide-amine Rh(i) compound (7), whereas reactions with the anionic NHSn 6 led to a Rh-fluorenyl complex of low stability with an uncoordinated pendent NHSn arm, which X-ray crystallography showed to be dimeric in the solid state.
authors.affiliation: Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK. s.mansell@hw.ac.uk.
authors.forename: Marta
authors.initials: M
authors.lastname: Roselló-Merino
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Mansell