Dimethylformamide → 1-(5-Iodo-4-hydroxy-3-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)butan-1,4-dione

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To 3-iodo-4-trimethylsilyloxy-5-methoxybenzaldehyde in 570 mL of seive dried DMF was added 3,4,5-trimethoxyphenylvinyl ketone from Example 1, Step B (179 g, 0.805 mole) and 3-ethyl-5-(2-hydroxyethyl)-4-methylthiazolium bromide (61.9 g, 0.24 mole). Triethylamine (320 mL) was added, and the resulting mixture was stirred at 70° C. under nitrogen atmosphere for 2 hours. The mixture was cooled, filtered, and washed with MeOH (500 mL). The resulting solution was cautiously acidified with 6 N HCL to pH 1.5 and a heavy yellow precipitate began to form. This mixture was stirred at room temperature for 2 hours to ensure complete desilylation. The precipitate was filtered, washed with H2O (4×1 L), and redissolved in a minimum volume of CH2Cl2. The solution was washed with brine, dried over anhydrous MgSO4, and evaporated in vacuo to provide a white solid. The solid was washed with MeOH and dried under high vacuum to provide 1-(5-iodo-4-hydroxy-3-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)butan-1,4-dione as a white solid, m.p. 189°-190° C.

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