p-Toluenesulfonic acid → HCID 12980024, compound

Participants

Reaction Conditions

Reaction Steps

2,6-Diisopropylaniline (3.8 mL, 20 mmol, Aldrich) was mixed with propiophenone (2.7 mL, 20 mmol, Aldrich) and p-TsOH (0.4 g, 2.1 mmol, Aldrich). The resulting mixture was heated at 205° C. for 1.5 h under a slow stream of Ar to remove H2O that formed. After cooling to RT the reaction mixture was poured into hexanes (50 mL), filtered, the precipitate was washed with additional hexanes (2×20 mL) followed by the evaporation of the filtrate and distillation of the residue. After the initial fraction of starting materials (80–110° C./0.5 mm) the product was collected as a yellow oil, bp 110–125° C./0.5 mm. Crystallization from methanol at −30° C. it afforded product as yellow crystals (4.3 g, 73.3%). 1H NMR (CDCl3) 7.99–7.91 (m, 2H); 7.54–7.44 (m, 3H); 7.20–7.13 (m, 2H); 7.12–7.04 (m, 1H); 2.78 (septet, 2H; J=6.9 Hz); 2.53 (q, 2H; J=7.7 Hz); 1.21 (d, 6H; J=6.9 Hz); 1.16 (d, 6H; J=6.9 Hz); 0.99 (t, 3H; J=7.7 Hz).

Provenance & Evidence