Fig. 1. Initial screening of known ligands for the copper-catalyzed coupling of representative amines and model DNA-conjugated aryl iodide 1a. Reaction conditions: A: 1a (1 nmol), 2a–f (500 mM), CuI (25 mM), ligand L (50 mM), K3PO4 (500 mM), DMSO (8 μl), water (8 μl), 40 °C, 3 h; B: 1a (1 nmol), 2a–f (500 mM), CuI (25 mM), ligand L (50 mM), sodium ascorbate (50 mM), K3PO4 (500 mM), DMSO (8 μl), water (8 μl), 40 °C, 3 h. Reactions performed in air. Pie chart areas represent conversion to 3a–f (%) as determined by UPLC-TOF.
