1: 2-(2,4,5-trifluorophenyl)acetic acid With 2,2-Dimethyl-[1,3]dioxane-4,6-dione; N-ethyl-N,N-diisopropylamine; 4-(N,N-dimethlyamino)pyridine in isobutyramide T=20 - 40°C; 2: With pivaloyl chloride in isobutyramide T=0 - 5°C; 1 - 3 h; 3: 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a] pyrazine hydrochloride in isobutyramide T=40 - 70°C;

1: 2,2-Dimethyl-[1,3]dioxane-4,6-dione; 2-(2,4,5-trifluorophenyl)acetic acid With 4-(N,N-dimethlyamino)pyridine; pivaloyl chloride; N-ethyl-N,N-diisopropylamine in acetonitrile T=45 - 55°C; Large scale reaction; 2: 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a] pyrazine hydrochloride With trifluoroacetic acid in acetonitrile T=50 - 55°C; 6 h; Large scale reaction;

4-methyl-morpholine in ethyl acetate 6 h; Reflux;

1: (2,3,4-trifluorophenyl)acetic acid With 1,1'-carbonyldiimidazole in isopropanol acetate T=45°C; 0.166667 h; 2: 2,2-Dimethyl-[1,3]dioxane-4,6-dione in isopropanol acetate T=20 - 40°C; 25.5 h; 3: 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a] pyrazine hydrochloride in isopropanol acetate T=90°C; 12 h;

1: in N,N-dimethyl acetamide T=40 - 70°C; 1 h; 2: With sodium hydrogencarbonate in N,N-dimethyl acetamide; water T=20 - 45°C; 3 - 5 h;

1: With sulfuric acid; sodium nitrite 2: With potassium dichromate

N-ethyl-N,N-diisopropylamine in toluene T=25 - 30°C; Reflux;

in N,N-dimethyl acetamide T=41.1°C; Kinetics; Further Variations:Temperatures;

methanesulfonic acid in acetonitrile T=25 - 85°C; Product distribution / selectivity;

1.1: 4-(N,N-dimethlyamino)pyridine / acetonitrile / 25 - 30 °C 1.2: 30 - 50 °C 2.1: hydrogenchloride / ethyl acetate; water / 0.5 h / 25 - 30 °C View Scheme