Compound 4

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Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

General Procedure for the Amination Reaction Using Amines – GP1: A tube equipped with a stirring bar was charged with NCS (1.0 equiv.), Ru(bpy)₃Cl₂ (5 mol%) and the amine (1.0 equiv.) if solid. The tube was capped with a Supelco aluminium crimp seal with septum (PTFE/butyl), evacuated and refilled with N₂ (x 3). The solvent (0.1M) (dry and degassed by bubbling through with N₂ for 20 min) and the amine (1.0 equiv.) if liquid were added and the mixture was stirred for 30/60 min in the dark. The arene (2.0 equiv.) and HClO₄ (4.0 equiv.) were added and the blue LEDs were immediately switched on. The mixture was stirred in front of blue LEDs for 2 h (in some cases the mixture was cooled to 0 °C just before blue LEDs irradiation, see below for individual examples). KOH (1 M in brine) and EtOAc were added and the mixture was shaken vigorously. The aqueous layer was extracted with EOAc (x 3), the combined organic layers were dried (MgSO₄), filtered and evaporated. Purification by flash column chromatography on silica gel gave the products. Following GP1 outlined above in 1,1,1,3,3,3-hexafluoro-i-propanol (HFIP), 2 (13 mg, 0.1 mmol) gave 4 and 4* (22 mg, 98%) as an oil. p:m = 7:1. ¹H NMR (500 MHz, CDCl₃) δ 7.30 (2H, d, J = 8.5 Hz), 6.92 (2H, d, J = 8.5 Hz), 3.14 (4H, t, J = 5.5 Hz), 1.75–1.71 (4H, m), 1.60–1.55 (2H, m), 1.31 (s, 9 H); ¹³C NMR (126 MHz, CDCl₃) δ 149.9, 141.9, 125.7, 116.2, 50.9, 33.9, 31.4, 26.0, 24.3.