Products > TCI Topics Archives > TCI Topics 2025 >

TCI Practical Example: The Synthesis of α-Aminoamide Catalyzed by a Visible Light Photoredox Catalyst

We are proud to present the synthesis of an α-aminoamide from N,N-dimethylaniline and p-toluenesulfonylmethyl isocyanide by using Ir[(ppy)₂(bpy)]PF₆ as a visible light photoredox catalyst.

Used Chemicals

• 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

Procedure

N,N-Dimethylaniline (0.18 g, 1.5 mmol, 1.0 eq.), TosMIC (0.439 g, 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 room temperature under nitrogen gas atmosphere. The mixture was placed at a distance of 2-3 cm from the Blue LED lamps. The orange solution was stirred at room temperature 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 brown solid (131 mg, 26% yield).

Experimenter’s Comments

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

Analytical Data

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.

Lead Reference

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

Other Reference

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