PROCESS FOR THE PREPARATION OF 5-(2,2,2,-TRIHALOGEN-ETHYL)-DIALKYL-TETRAHYDROFURAN-2-ONES

摘要

Preparation of 5-(2,2,2-trihaloethyl)-4,4-dialkyl-tetrahydro-furan-2-ones of the formula I IMAGE (I) where R1 and R2 are each alkyl of 1 to 4 carbon atoms and X is halogen, by reacting a carboxylic acid amide of the formula II IMAGE (II) where R3 and R4 are each alkyl of 1 to 4 carbon atoms, aralkyl of 7 to 9 carbon atoms or aryl of 6 to 10 carbon atoms or together with the nitrogen on which they are present as substituents form a 5-membered or 6-membered saturated ring which may contain a second hetero-atom, with a carbon tetrahalide of the formula III CX4 (III) to give an iminium salt of the formula IV IMAGE (IV) and subsequently hydrolyzing this iminium sa and novel iminium salts of the formula IV.