Benzaldehyde → Dalosirvat

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Triethylamine (3.61 mmol) and benzaldehyde (4.3 mmol) in dry dioxane (10 mL) was added to a solution of 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-3-(dimethylamino)propan-1-one (XVI) (5.4 mmol) and 3-ethyl-5-(2-hydroxyethyl)-4-methylthiazolium bromide (0.43 mmol) in dioxane heated at 95° C. under nitrogen. The solution was further heated overnight at 95° C. The solution was cooled and excess solvent was evaporated under vacuum. The residue was partitioned between CH2Cl2 and water. The organic phase was dried over MgSO4, filtered and concentrated. The residue was purified by flash chromatography eluting with ethyl acetate in hexane gradient to yield 1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-4-phenylbutane-1,4-dione 1 as a white solid (12% yield). 1H NMR (DMSO-d6, 400 MHz): δ ppm 3.33-3.37 (m, 4H), 4.29 (m, 2H), 4.34 (m, 2H), 6.98 (m, 1H), 7.48 (m, 1H), 7.55 (m, 3H), 7.64 (m, 1H), 8.00-8.02 (m, 2H); ESIMS found C18H16O4 m/z 297 (M+H).

Herkunft & Nachweise