Triphenylphosphine → 2-(4'-Fluorophenyl)-4-[4'-(3-dimethylamino-2-propyn-1-yl)phenyl]thiazole

Participants

Reaction Steps

In a 100 ml flask is placed triphenylphosphine (80 mg, 10%), PdCl2 (40 mg, 5%) and 2-(4′-fluorophenyl)-4-(4′-bromophenyl)thiazole (0.98 g, 2.9 mmol) in 20 mL of diethylamine. After stirring for 15 min under N2 atmosphere, CuI (30 mg, 5%) and 1-dimethylamino-2-propyne (0.27 g, 3.18 mmol) in 20 ml of acetonitrile are added to the mixture. After 18 h of heating, the solvent is evaporated under reduced pressure and the residue is filtered through silica gel pad (50 g) using CHCl3 (400 mL) and 2% MeOH in CHCl3(400 mL). A large portion of unreacted 2-(4′-fluorophenyl)-4-(4′-bromophenyl)thiazole is recovered after removal of chloroform filtrate (0.55 g, 56%). The second part of the filtrate (2% MeOH in CHCl3) is concentrated and the residual solid is then purified over silca gel column eluting with 2% MeOH in CHCl3. 2-(4′-fluorophenyl)-4-[4′-(3-dimethylamino-2-propyn-1-yl)phenyl]thiazole is obtained after concentration and trituration with hexane (0.25 g, 27% yield), mp. 98-9° C. 1H NMR (CDCl3): δ 2.39 (s, 6H), 3.50 (s, 2H), 7.16 (t, 2H), 7.48 (s, 1H), 7.51 (d, 2H), 7.93 (d, 2H), 8.03 (m, 2H).

Provenance & Evidence