5-chloro-2-hydroxybenzohydrazide

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5-chlorosalicylhydrazide (213.9 mg, 1.2 mmol), 3,5-bis(trifluoromethyl)benzaldehyde (190 μL, 1.2 mmol), concentrated sulfuric acid (3 drops) and ethanol (5 mL) was refluxed for 30 minutes. 3,5-Bis(trifluoromethyl)benzaldehyde (100 μL, 0.61 mmol) was added and the mixture was refluxed for further 1 hour. After the reaction mixture was cooled to room temperature, it was poured into water and extracted with ethyl acetate. After the ethyl acetate layer was washed with brine, dried over sodium sulfate, the residue obtained by evaporation of the solvent under reduced pressure was purified by column chromatography on silica gel (n-hexane:ethyl acetate=3:1→2:1) and washed with n-hexane under suspension to give the title compound (362.6 mg, 76.8%) as a white powder. was refluxed for 30 minutes the mixture was refluxed for further 1 hour extracted with ethyl acetate After the ethyl acetate layer was washed with brine dried over sodium sulfate the residue obtained by evaporation of the solvent under reduced pressure was purified by column chromatography on silica gel (n-hexane:ethyl acetate=3:1→2:1) washed with n-hexane under suspension

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5-chloro-2-hydroxybenzoic acid methyl ester (0.50 g, 2.7 mmol), hydrazine monohydrate (0.3 mL, 6.2 mmol) and ethanol (5 mL) was refluxed for 6 hours. After the reaction mixture was cooled to room temperature, n-hexane was added and the separated crystal was filtered to give the title compound (395.9 mg, 79.2%) as a white crystal. was refluxed for 6 hours the separated crystal was filtered

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5-chloro-2-hydroxybenzoic acid methyl ester (0.50 g, 2.7 mmol), hydrazine monohydrate (0.3 mL, 6.2 mmol) and ethanol (5 mL) was refluxed for 6 hours. After the reaction mixture was cooled to room temperature, n-hexane was added and the separated crystal was filtered to give the title compound (395.9 mg, 79.2%) as a white crystal. was refluxed for 6 hours the separated crystal was filtered

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 37.2 g of 5-chloro-2-hydroxybenzoic acid hydrazide are dissolved in 200 ml of dimethylacetamide and 16 g of pyridine and 22 g of chloroformic acid ethyl ester are added simultaneously over the course of 30 minutes. The reaction mixture is subsequently heated to 90° C for 3 hours whilst stirring, cooled and poured onto 1 litre of ice water. The precipitate which has separated out slowly crystallises throughout. The N-(5-chloro-2-hydroxybenzoyl)-hydrazinecarboxylic acid ethyl ester thus obtained (Stabiliser No. 11) is isolated, washed with water and recrystallised from ethanol. Melting point 172° C. cooled The precipitate which has separated out slowly crystallises throughout

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5-chlorosalicylhydrazide (213.9 mg, 1.2 mmol), 3,5-bis(trifluoromethyl)benzaldehyde (190 μL, 1.2 mmol), concentrated sulfuric acid (3 drops) and ethanol (5 mL) was refluxed for 30 minutes. 3,5-Bis(trifluoromethyl)benzaldehyde (100 μL, 0.61 mmol) was added and the mixture was refluxed for further 1 hour. After the reaction mixture was cooled to room temperature, it was poured into water and extracted with ethyl acetate. After the ethyl acetate layer was washed with brine, dried over sodium sulfate, the residue obtained by evaporation of the solvent under reduced pressure was purified by column chromatography on silica gel (n-hexane:ethyl acetate=3:1→2:1) and washed with n-hexane under suspension to give the title compound (362.6 mg, 76.8%) as a white powder. was refluxed for 30 minutes the mixture was refluxed for further 1 hour extracted with ethyl acetate After the ethyl acetate layer was washed with brine dried over sodium sulfate the residue obtained by evaporation of the solvent under reduced pressure was purified by column chromatography on silica gel (n-hexane:ethyl acetate=3:1→2:1) washed with n-hexane under suspension

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5-chloro-2-hydroxybenzoic acid methyl ester (0.50 g, 2.7 mmol), hydrazine monohydrate (0.3 mL, 6.2 mmol) and ethanol (5 mL) was refluxed for 6 hours. After the reaction mixture was cooled to room temperature, n-hexane was added and the separated crystal was filtered to give the title compound (395.9 mg, 79.2%) as a white crystal. was refluxed for 6 hours the separated crystal was filtered