Process Study On The Synthesis Of N-substituted Amide Via Ritter Reaction

Synthetic method of alkyl acrylamides via Ritter reaction in aquous sulfuric acid or acidic ionic liquid was studied in this dissertation.Reaction of acetone with acrylonitrile in aquous sulfuric acid gave a product, diacetone acrylamide. The reaction was carried out in aqueous sulfuric acid without the presence of any organic solvent. Under optimized conditions, i.e. at 55℃for 6 hours with molar ratio of acetone, acrylonitrile and sulfuric acid (95%) 2:1.5:2.5, the yield of diacetone acrylamide was up to 70%. Recrystallization of the crude diacetone acrylamide in n-hexane gave purified product in 82% yield.Ritter reaction of isopropyl acetate and acrylonitrile in aquous sulfuric acid gave N-isopropylacrylamide.Under optimized conditions, i.e. at 65℃for 2 hours with molar ratio of acrylonitrile, isopropyl acetate and concentrated sulfuric acid 1.0:1.5:3.0 in the presence of 0.1g hydroquinone, the yield of the product was up to 70%.Reaction of tert-butyl alcohol and phenylacetonitrile in ionic liquids, [MIMBS]HSO4 and [TEBSA]HSO4, gave a product of N-tert-butyl-2-phenyl acetamide. When the reaction was carried out in [MIMBS]HSO4 with molar ratio of tert-butyl alcohol, phenylacetonitrile and [MIMBS]HSO4 1.2:1:2 for 4 hour at 75℃, the yield of the product was 62%.99% of the ionic liquid was recovered and reused in the reaction. The yield of the product was 47% after recycling 5 times. When the reaction was carried out in [TEBSA]HSO4 with molar ratio of tertbutyl alcohol, phenylacetonitrile and[TEBSA]HSO4 1.2:1:2 for 6 hour at 75℃, the product was obtained in 70% yield.99% of the ionic liquid was recovered and reused in the reaction. The yield of the product was 60% after recycling 5 times.