Scheme 2. Scope for iron- and cobalt-catalysed hydrosilylation reactions enabled by tetrafluoroborate activation. (a) Reaction conditions: olefin, PhSiH3 (1.1 eq.), EtBIP (2 mol%) and Fe(BF4)2·6H2O (2 mol%), THF, r.t., 4 h. †MesBIP (2 mol%) used. (b) Reaction conditions: olefin, PhSiH3 (1.1 eq.), EtBIP (2 mol%) and Co(BF4)2·6H2O (2 mol%), THF, r.t., 4 h. (c) Reaction conditions: alkene (1 equiv.), PhSiH3 (1 equiv.) Fe(BF4)2·6H2O (2 mol%), EtBIP (2 mol%), THF, r.t., 30 min then a second alkene (1 equiv.) added, 3 h. Yields determined by 1H NMR spectroscopy of the crude reaction mixture using 1,3,5-trimethoxybenzene as an internal standard, isolated yields in parenthesis.
