Synthesis of Mono-, Bis- and Tris(pentafluoroethyl)tin Derivatives, (C2F5)4−nSnXn (X=Ph, Me, Cl, Br, Cp; n=1–3)

5 years ago

Synthesis of Mono-, Bis- and Tris(pentafluoroethyl)tin Derivatives, (C2F5)4−nSnXn (X=Ph, Me, Cl, Br, Cp; n=1–3)

Mark Niemann, Beate Neumann, Markus Wiesemann, Johannes Klösener, Berthold Hoge, Hans-Georg Stammler

For (pentafluoroethyl)phenylstannanes, (C2F5)4−n SnPhn (n=1–3), and dimethylbis(pentafluoroethyl)stannane, (C2F5)2SnMe2, a high yield synthesis was developed by the use of LiC2F5 as a C2F5 transfer reagent. The treatment of these products with gaseous hydrogen chloride or hydrogen bromide afforded (C2F5)4−nSnXn (X=Cl, Br; n=1–3) in good yields. The (pentafluoroethyl)stannanes were fully characterized by 1H, 13C, 19F and 119Sn NMR, IR spectroscopy and mass spectrometry. The treatment of the (pentafluoroethyl)tin halides (C2F5)4−nSnXn with 1,10-phenanthroline (phen) led to the formation of the corresponding octahedrally coordinated complexes [(C2F5)4−nSnXn(phen)], the structures of which were elucidated by X-ray diffraction analyses. The bromostannane (C2F5)3SnBr reacted with sodium cyclopentadienide to give the (η1-cyclopentadienyl)tris(pentafluoroethyl)stannane, (C2F5)3SnCp, for which single-crystal X-ray diffraction analysis could be performed. The coupling constants 1J(119Sn,13C) and 2J(119Sn,19F) of all new stannanes are strongly correlated and sensitive to the substitution pattern at the tin atom. For both coupling constants a negative sign could be assigned. Some-tin special: We present a convenient protocol for the high yield synthesis of (pentafluoroethyl)stannanes (n=1–3) by using LiC2F5. (Pentafluoroethyl)phenylstannanes are functionalized by gaseous hydrogen halides HX (X=Cl, Br) to give (pentafluoroethyl)tin halides. Their corresponding 1,10-phenanthroline (phen) complexes were structurally characterized by X-ray diffraction analysis.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201701270