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41295-65-2

4-Chloromethyl-6-methyl-chromen-2-one ,97% synthesis

4synthesis methods
-

Yield:41295-65-2 86%

Reaction Conditions:

with sulfuric acid in water at 20; for 18 h;

Steps:

62

To a mixture of 4-methy I phenol (21.6 g, 200 mmol) and 4-chloro-3-oxo-butyric acid ethyl ester (32.9 g, 200 mmol) is added dropwise during 30 min. at 00C a mixture of concentrated sulfuric acid (180 mL) and water (60 ml_). The resulting clear solution is stirred for 18 h at room temperature, during which time a white precipitate is formed. The reaction mixture is poured over crushed ice (1 kg) and the formed precipitate is collected, washed with water and dried in vacuo at 50 0C to yield the title compound as a white powder (35.8 g, 172 mmol, 86 %). 1H NMR (400 MHz, CDCI3, 298 K): δ = 7.45 (s, 1 H), 7.40 (d, J = 8.6 Hz, 1 H), 7.29 (d, J = 8.6 Hz, 1H), 6.58 (s, 1H), 4.69 (s, 1 H), 2.46 (s, 3H).

References:

WO2008/74752,2008,A2 Location in patent:Page/Page column 38