tert-butyl 4,4-difluoroazepane-1-carboxylate

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

Procedure: To 830 mg (3.53 mmol) of 4,4-Difluoro-perhydro-azepine-1-carboxylic acid tert-butyl ester was added 5 mL of 2 M aq. HCl and stirring was continued overnight at room temperature. The reaction mixture was freeze dried and used for the next step without further purification dried used for the next step without further purification

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

Procedure: Acetyl chloride (3.9 mL) was added to methanol (90 mL) at 0° C. and stirred for 20 minutes before addition of 4,4-difluoro-azepane-1-carboxylic acid tert-butyl ester as a solution in methanol (10 mL). After 30 minutes, HCl in dioxane (4 N, 40 mL) was added cautiously and the mixture was stirred at room temperature for 3 hours. The solution was concentrated, triturated with ether, filtered and dried under vacuum overnight to afford the title compound as an off-white solid (2.1 g). 1H NMR (400 MHz, DMSO): δ 9.5 (s, 2H), 3.2-3.1 (m, 4H), 2.5-2.4 (m, 2H), 2.3-2.2 (m, 2H), 1.9-1.8 (m, 2H). The solution was concentrated triturated with ether filtered dried under vacuum overnight

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

Procedure: Acetyl chloride (3.9 mL) was added to methanol (90 mL) at 0° C. and stirred for 20 minutes before addition of 4,4-difluoro-azepane-1-carboxylic acid tert-butyl ester as a solution in methanol (10 mL). After 30 minutes, HCl in dioxane (4 N, 40 mL) was added cautiously and the mixture was stirred at room temperature for 3 hours. The solution was concentrated, triturated with ether, filtered and dried under vacuum overnight to afford the title compound as an off-white solid (2.1 g). 1H NMR (400 MHz, DMSO): δ 9.5 (s, 2H), 3.2-3.1 (m, 4H), 2.5-2.4 (m, 2H), 2.3-2.2 (m, 2H), 1.9-1.8 (m, 2H). The solution was concentrated triturated with ether filtered dried under vacuum overnight

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

Procedure: To 830 mg (3.53 mmol) of 4,4-Difluoro-perhydro-azepine-1-carboxylic acid tert-butyl ester was added 5 mL of 2 M aq. HCl and stirring was continued overnight at room temperature. The reaction mixture was freeze dried and used for the next step without further purification dried used for the next step without further purification