Triethylamine → 5-(2-Aminophenylethynyl)-2,4-dimethoxybenzaldehyde

Participants

Reaction Steps

Ex-35C: To a solution of 5-iodo-2,4-dimethoxybenzaldehyde (Ex-35B, 11.7 g, 40 mmol) in 250 ml of THF, PdCl2(PPh3)2 (0.56 g, 0.8 mmol), CuI (0.3 g, 1.6 mmol), Et3N (6.06 g, 60 mmol), and 2-[(trimethylsilyl)ethynyl]aniline (7.92 g, 42 mmol) were added. The mixture was stirred to a homogeneous solution, and then TBAF (10.4 g, 40 mmol) was added. The reaction mixture was aged at room temperature for 4 h and then filtered. The filtrate was concentrated to about 50 ml, and the precipitate was filtered to give first portion of 5-(2-aminophenylethynyl)-2,4-dimethoxybenzaldehyde (8.5 g), as light yellow crystals. The filtrate was concentrated, and the residue was recrystallized from EtOAc/hexanes to give 1.85 g of additional product (total 10.35 g, 92%), mp 180–181° C. 1H-NMR (300 MHz, CDCl3) δ 10.30 (s, 1H), 7.99 (s, 1H), 7.36 (d, J=8 Hz, 1H), 7.11–7.17 (m, 1H), 6.69–6.75 (m, 2H), 6.46 (s, 1H), 4.41 (brs, 2H), 4.02 (s, 3H), 4.00 (s, 3H). HRMS Calcd. for C17H15NO3: 281.1052 (M+); Found: 281.1056. Anal. Calcd. for C17H15NO3: C, 72.58; H, 5.37; N, 4.98; Found: C, 72.74; H, 5.38; N, 4.93.

Provenance & Evidence