ethyl 1-bromocyclobutane-1-carboxylate

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

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

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

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

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

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

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

Conditions: temp:65.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2,3-dichloro-4-butyrylphenol (7 g, 0.03 mole), ethyl 1-bromocyclobutanecarboxylate (10.23 g, 0.049 mole) and potassium carbonate (7.5 g, 0.054 mole) in N,N-dimethylformamide (60 ml) was stirred and heated at 65° C. for 18 hours. The reaction mixture was poured into ice water and the resulting mixture was extracted with ether. The ether extract was washed with a 1% sodium hydroxide solution, then with water and finally dried over MgSO4. The ether was evaporated in vacuo and the residue treated with acetic acid (60 ml) and 5% hydrochloric acid (15 ml). The mixture was stirred and refluxed overnight. The solvents were evaporated in vacuo. The residue was chromatographed over a column containing silica gel (140 g) using methylene chloride/tetrahydrofuran/acetic acid 50/1/1 as the eluent. The pertinent fractions were united, treated with toluene and evaporated in vacuo to obtain 1-(2,3-dichloro-4-butyrylphenoxy)cyclobutane-1-carboxylic acid as a liquid whose identity was confirmed by NMR and purity by thin layer chromatography. the resulting mixture was extracted with ether The ether extract was washed with a 1% sodium hydroxide solution with water and finally dried over MgSO4 The ether was evaporated in vacuo the residue treated with acetic acid (60 ml) and 5% hydrochloric acid (15 ml) The mixture was stirred refluxed overnight The solvents were evaporated in vacuo The residue was chromatographed over a column containing silica gel (140 g) treated with toluene evaporated in vacuo

Conditions: temp:65.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2,3-dichloro-4-butyrylphenol (7 g, 0.03 mole), ethyl 1-bromocyclobutanecarboxylate (10.23 g, 0.049 mole) and potassium carbonate (7.5 g, 0.054 mole) in N,N-dimethylformamide (60 ml) was stirred and heated at 65° C. for 18 hours. The reaction mixture was poured into ice water and the resulting mixture was extracted with ether. The ether extract was washed with a 1% sodium hydroxide solution, then with water and finally dried over MgSO4. The ether was evaporated in vacuo and the residue treated with acetic acid (60 ml) and 5% hydrochloric acid (15 ml). The mixture was stirred and refluxed overnight. The solvents were evaporated in vacuo. The residue was chromatographed over a column containing silica gel (140 g) using methylene chloride/tetrahydrofuran/acetic acid 50/1/1 as the eluent. The pertinent fractions were united, treated with toluene and evaporated in vacuo to obtain 1-(2,3-dichloro-4-butyrylphenoxy)cyclobutane-1-carboxylic acid as a liquid whose identity was confirmed by NMR and purity by thin layer chromatography. the resulting mixture was extracted with ether The ether extract was washed with a 1% sodium hydroxide solution with water and finally dried over MgSO4 The ether was evaporated in vacuo the residue treated with acetic acid (60 ml) and 5% hydrochloric acid (15 ml) The mixture was stirred refluxed overnight The solvents were evaporated in vacuo The residue was chromatographed over a column containing silica gel (140 g) treated with toluene evaporated in vacuo

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

Procedure: Prepared as described in general procedure (H) using 1-cyclohexyl-1-(trans-4-methyl-cyclohexyl)-3-(5-thiocyanato-thiazol-2-yl)-urea, dithioerythritol and ethyl-1-bromocyclobutane carboxylate. Prepared

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

Procedure: Prepared as described in general procedure (H) using 1-cyclohexyl-1-(trans-4-methyl-cyclohexyl)-3-(5-thiocyanato-thiazol-2-yl)-urea, dithioerythritol and ethyl-1-bromocyclobutane carboxylate. Prepared

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

Procedure: A solution of 5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-triazole-3-thiol (100 mg, 0.289 mmol), ethyl 1-bromocyclobutanecarboxylate (47 μL, 0.289 mmol) and diisopropylethylamine (15 μL, 0.866 mmol) in DMF (1 mL) was heated at 60° C. for 4 days. After cooling to room temperature, the mixture was concentrated and partitioned between dichloromethane (15 mL) and HCl (1N aqueous, 15 mL). The aqueous layer was extracted with dichloromethane (2×15 mL) and the combined organic extracts dried over sodium sulfate, concentrated and purified by column chromatography (40% EtOAc/hexanes) to provide ethyl 1-(5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-triazol-3-ylthio)cyclobutanecarboxylate as a light yellow sticky foam (75 mg, 55% yield). the mixture was concentrated partitioned between dichloromethane (15 mL) and HCl (1N aqueous, 15 mL) The aqueous layer was extracted with dichloromethane (2×15 mL) the combined organic extracts dried over sodium sulfate concentrated purified by column chromatography (40% EtOAc/hexanes)