Dichloroacetyl chloride → HCID 87197691, compound

Participants

Reaction Steps

At room temperature, dichloroacetyl chloride (50 g, 0.339 mol) was added dropwise (slightly exothermic) to a suspension of AlCl3 (45 g, 0.339 mol) in 1,2-dichloroethylene (49.3 g, 0.508 mol). The reaction mixture was stirred under reflux conditions for 3 h and then at room temperature overnight. The reaction mixture was then stirred into ice water (500 g) (foams and reacts violently) and extracted three times with methylene chloride (200 ml). The combined organic phases were washed once at 10° C. with a saturated aqueous NaHCO3 solution and dried over magnesium sulfate, and the solvent was removed at a bath temperature of 70° C. at atmospheric pressure. The residue was subjected to incipient distillation at 50 mbar and 70° C. This gives 46.5 g of a black oil having a (Z)-1,1,3,4-tetrachlorobut-3-en-2-one content of about 70% and contains 25% of a byproduct, which is (Z)-1,1,1,4-tetrachlorobut-3-en-2-one. Accordingly, the yield of (Z)-1,1,3,4-tetrachlorobut-3-en-2-one is 38%.

Provenance & Evidence