Production of chloroalkanoyl chloride, such as 5-chlorovaleryl chloride, used in synthesis of active pharmaceutical and agrochemical compounds, comprises introducing hydrogen chloride during heat-up in catalytic phosgenation of lactone

摘要

In the production of chloroalkanoyl chlorides (I) with a (substituted) 1-10 carbon (hetero)alkylene chain by reacting a lactone (II) with hydrogen chloride (HCl) and phosgene (COCl2) in the presence of a catalyst, HCl is introduced before and/or during addition of COCl2, starting when the temperature reaches >= 60 deg C, and the catalyst is a pyridine compound. In the production of chloroalkanoyl chlorides of formula (I) with a (substituted) 1-10 carbon (hetero)alkylene chain by reacting a lactone of formula (II) with hydrogen chloride (HCl) and phosgene (COCl2) in the presence of a catalyst, HCl is introduced before and/or during addition of COCl2, starting when the temperature reaches >= 60 deg C, and the catalyst is a pyridine compound: R<1>, R<2> = H or R; R = halogen, nitro, CN or an organic group containing carbon (C); Y = optionally R-substituted 1-10 C alkylene, which may have a (thio)ether, tertiary amino or keto group in the chain, in which R groups on Y, R<1> and/or R<2> may be linked to form a non-aromatic system.