Fig. 3: Substrate scope of iron-catalyzed methylzincation of terminal alkynes.
From: Iron-catalyzed alkyne alkylzincation affected by counterions
Reaction conditions: alkynes (0.5 mmol, 1.0 equiv), Me2Zn (1 M in toluene, 0.55 mmol, 550 μL, 1.1 equiv), [Fe] cat. (0.01 mmol, 2 mol%), NaBArF4 (0.025 mmol, 5 mol%), solvent (2 mL). The reactions quenched with D2O (150 μL) or I2 (3.0 equiv), isolated yields were given. a Used C3 as pre-catalyst, PhCF3 as solvent, −20 °C, 1 h, rt (~30 °C), 2 h. b Used C3 as pre-catalyst, toluene as solvent, -78 °C to 0 °C, 3 h. c Quenched with PhC(O)Cl (3.0 equiv), CuCN (20 mol%), THF/PhCF3 = 1:1. d Used C2 as pre-catalyst, toluene as solvent, rt (~30 °C), 3 h. e Used C1 as pre-catalyst and PhCF3 as solvent rt (~30 °C), 3 h.
