1,4-DICHLORO-3-BUTEN-2-ONE synthesis

Yield:69711-44-0 82%

Reaction Conditions:

aluminium chloride in tetrachloromethane;water;

Steps:

1 Preparation of 1,4-dichlorobut-3-en-2-one

EXAMPLE 1 Preparation of 1,4-dichlorobut-3-en-2-one Aluminium chloride (39.9 g, 0.3 mol) in carbon tetrachloride (150 ml) was treated with chloroacetylchloride (22.3 ml, 0.3 mol) while acetylene was passed through the reaction mixture. Acetylene addition was continued with stirring for 3 hours. Water was added to the reaction mixture, which was extracted with ether. The combined ether extracts were washed with saturated brine, N sodium bicarbonate solution, saturated brine, dried and evaporated to give the crude title compound (34.1 g, 82%) as a mixture of cis and trans isomers. Cis isomer δ (CDCl₃) 4.32 (2H, s, CH₂), 6.66 (1H, d, 8 Hz, --CH=), 6.88 (1H, d, J 8 Hz, --CH=), trans isomer δ (CDCl₃) 4.22 (2H, s, CH₂), 6.82 (1H, d, J 14 Hz, CH=), 7.52 (1H, d, J 14 Hz, CH=). ν_max (film) 1580, 1690 cm^-1.

References:

US4252976,1981,A