Potassium Chloride → 3-(2-Chloro-4-methoxy-phenyl)-propenal

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a mixture of 4-bromo-3-chloro anisole (35 g, 0.159 mol), KCl (11.9 g, 0.160 mol, 1 eq.), K2CO3 (33 g, 0.238 mol, 1.5 eq) in 400 mL DMF in a sealed tube was added acrolein diethylacetal (73 mL, 0.479 mol, 3 eq.) and Bu4NOAc (96 g, 0.318 mol, 2 eq.). N2 was bubbled through the mixture and Pd(OAc)2 (1.1 g, 4. mmol, 3 mol %) was added. The reaction mixture was heated in an oil bath for 6 hr at 100° C. then cooled in an ice-bath. 300 mL of water was then added, followed by 500 mL of 1N HCl. The ice-bath was removed and the mixture was stirred for 30 min. The solution was extracted with ethyl acetate once then with diethyl ether 3 times. The combined organic layer washed with water, brine, dried over MgSO4, filtered and concentrated to provide the crude product which was recrystallized from hot ethyl acetate-hexanes to provide 15.5 g of crystalline 3-(2-chloro-4-methoxy-phenyl)-propenal. The mother liquor was concentrated and chromatographed with 10% ethyl acetate to provide another 5.6 g of 3-(2-chloro-4-methoxy-phenyl)-propenal.

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