Design of New Reaction Conditions for the Sugasawa Reaction Based on Mechanistic Insights

摘要: A process to prepare 2-propionyl-4-bromoaniline by ortho acylation of 4-bromoaniline under Sugasawa conditions was developed. Upon scale-up in a pilot plant, the gave lower yields than laboratory four out five plant runs. Analysis pilot-plant data, conjunction with reaction calorimetric experiments, showed that expulsion HCl from medium key for obtaining high product yields. New were subsequently developed carrying (1). The mixture containing aniline/BCl3/AlCl3/C2H5CN added refluxing solution toluene allow substantial and thus obtain optimum yield desired product. Aniline hydrochlorides also shown be suitable starting materials these conditions. Mechanistic implications findings are discussed. new significantly increased yield.