(2,2'-Bipyridine)bis(2-phenylpyridinato)iridium(III) Hexafluorophosphate

• N,N-Dimethylaniline [D0665]
• p-Toluenesulfonylmethyl Isocyanide (= TosMIC) [T1046]
• (2,2'-Bipyridine)bis(2-phenylpyridinato)iridium(III) Hexafluorophosphate (= Ir[(ppy)₂(bpy)]PF₆ [B4893]
• Acetonitrile
• Ion-Exchanged Water

N,N-Dimethylaniline (0.18 g, 1.5 mmol, 1.0 eq), TosMIC (0.439g, 2.25 mmol, 1.5 eq), Ir[(ppy)₂(bpy)]PF₆ (12 mg, 0.015 mmol, 1.0 mol%), ion-exchanged water (0.27 mL, 15 mmol, 10 eq) were dissolved in acetonitrile (10 mL) at rt under N₂. The mixture was placed at a distance of 2-3 cm from Blue LED lamp. The orange solution was stirred at rt under visible light irradiation. After 2 days of irradiation, the solvent was removed in vacuo and the resulting residue was purified by column chromatography on silica gel (hexane:ethyl acetate = 9:1 – 1:1 - 0:1) to give compound 1 as a light blown solid (131 mg, y. 26%).

Acetonitrile was degassed with nitrogen for 1 hour before use.
Irradiation of visible light was performed with Kessil A160WE Tuna Blue 40W×2.
The reaction mixture was monitored by ¹H NMR and TLC (hexane:ethyl acetate = 1:1, Rf = 0.23).

Compound 1

¹H NMR (400 MHz, CDCl₃); δ 7.72 (d, J = 8.2 Hz, 2H), 7.34-7.27 (m, 5H), 6.89 (t, J = 6.9 Hz, 1H), 6.67 (d, J = 8.7 Hz, 2H), 4.69 (d, J = 6.9 Hz, 2H), 3.75 (s, 2H), 2.99 (s, 3H), 2.45 (s, 3H).

¹³C NMR (101 MHz, CDCl₃); δ 170.3, 148.9, 145.6, 133.6, 129.9, 129.4, 128.8, 119.2, 113.3, 59.8, 58.5, 40.0, 21.8.

• Visible Light Photoredox-Catalyzed Multicomponent Reactions
• M. Rueping, C. Vila, Org. Lett. 2013, 15, 2092.

• (review) A Retrosynthetic Approach for Photocatalysis
• D. Petzold, M. Giedyk, A. Chatterjee, B. Konig, Eur. J. Org. Chem. 2019, 10, 1193.