Fig. 2: Counterion effects of iron-catalyzed alkylzincation of alkynes.
From: Iron-catalyzed alkyne alkylzincation affected by counterions
Reaction conditions: alkynes (0.5 mmol, 1.0 equiv), Me2Zn or Et2Zn (1 M in toluene, 0.55 mmol, 550 μL, 1.1 equiv), Cat. (0.01 mmol, 2 mol%), NaBArF4 (0.025 mmol, 0.05 mol%). The reactions were quenched with D2O (150 μL), rt (~30 °C), 30 min. aUsed C3 as pre-catalyst, PhCF3 (2 mL), −20 °C, 1 h, rt (~30 °C), 2 h. bUsed C2 as pre-catalyst, toluene (2 mL), rt (~30 °C), 3 h. cUsed C1 as pre-catalyst, PhCF3 (2 mL), rt (~30 °C), 3 h. Yields were determined by 1H NMR use 1,3,5-(OMe)3C6H3 as internal standard.
