1-chloroethyl propan-2-yl carbonate

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: The title compound was prepared according to the procedure as described in Example 26 step 2 using N-(3-(5-(4-chlorophenyl)-1H-pyrrolo[2,3-b]pyridine-3-carbonyl)-2,4-difluorophenyl)propane-1-sulfonamide (0.3 g, 0.61 mmol), KOH (69 mg, 1.23 mmol) in anhydrous DMF (2 mL), a solution of TBAB (396 mg, 1.23 mmol) in anhydrous DMF (0.5 mL) and a solution of 1-chloroethyl isopropyl carbonate (101 mg, 0.61 mmol) in anhydrous DMF (0.5 mL). The crude product was purified by a silica gel column chromatography (PE/EtOAc (v/v)=5/1), and recrystallized in methanol to afford the title compound as a white solid (42 mg, 11.1%). The title compound was characterized by LC-MS and 1H NMR as shown below: The title compound was prepared The crude product was purified by a silica gel column chromatography (PE/EtOAc (v/v)=5/1) recrystallized in methanol

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1-chloroethyl carbonochloridate (10 g, 69.9 mmol) in DCM (200 mL) was added a solution of isopropanol (5.9 mL, 76.9 mmol) and pyridine (6.75 mL, 83.9 mmol) in DCM (50 mL) at −20° C. The reaction was stirred at 0° C. for 2 h, then at rt for another 2 h. The mixture was washed with 1N HCl solution (250 mL×2), followed by brine (250 mL). The organic phase was dried over anhydrous Na2SO4 and concentrated in vacuo to give the title compound as colorless oil (9.6 g, 82.4%). The product was used in the next step without further purification. The title compound was characterized by 1H NMR as shown below: at rt for another 2 h The mixture was washed with 1N HCl solution (250 mL×2) The organic phase was dried over anhydrous Na2SO4 concentrated in vacuo

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

Procedure: In a manner similar to the method described in Example 3, 1-chloroethyl chloroformate (Oakwood Products, 1.99 g, 1.5 mL, 13.9 mmol) was reacted with 2-propanol (785 mg, 1 mL, 13.0 mmol) and pyridine (1.27 g, 1.3 mL, 16.1 mmol) in methylene chloride (11 mL) at room temperature for 4 h to give 1-chloroethyl isopropyl carbonate. A portion of 1-chloroethyl isopropyl carbonate (221.6 mg, 1.33 mmol) was then reacted with chiral 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-3-methoxybenzoic acid (150.3 mg, 244 μmol) in the presence of cesium carbonate (478 mg, 1.47 mmol) in dimethylformamide (5 mL) overnight to give, after flash chromatography purification (hexane/ethyl acetate, 80/20 to 20/80), 1-(isopropoxycarbonyloxy)ethyl 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-3-methoxybenzoate (134.4 mg, 73% yield). MS (ES+) m/z calcd. for C37H40Cl2F2N3O7: [(M+H)+]: 746, found: 746 to give

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

Procedure: In a manner similar to the method described in Example 3, 1-chloroethyl chloroformate (Oakwood Products, 1.99 g, 1.5 mL, 13.9 mmol) was reacted with 2-propanol (785 mg, 1 mL, 13.0 mmol) and pyridine (1.27 g, 1.3 mL, 16.1 mmol) in methylene chloride (11 mL) at room temperature for 4 h to give 1-chloroethyl isopropyl carbonate. A portion of 1-chloroethyl isopropyl carbonate (221.6 mg, 1.33 mmol) was then reacted with chiral 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-3-methoxybenzoic acid (150.3 mg, 244 μmol) in the presence of cesium carbonate (478 mg, 1.47 mmol) in dimethylformamide (5 mL) overnight to give, after flash chromatography purification (hexane/ethyl acetate, 80/20 to 20/80), 1-(isopropoxycarbonyloxy)ethyl 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-3-methoxybenzoate (134.4 mg, 73% yield). MS (ES+) m/z calcd. for C37H40Cl2F2N3O7: [(M+H)+]: 746, found: 746

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

Procedure: In a manner similar to the method described in Example 3, 1-chloroethyl chloroformate (Oakwood Products, 1.99 g, 1.5 mL, 13.9 mmol) was reacted with 2-propanol (785 mg, 1 mL, 13.0 mmol) and pyridine (1.27 g, 1.3 mL, 16.1 mmol) in methylene chloride (11 mL) at room temperature for 4 h to give 1-chloroethyl isopropyl carbonate. A portion of 1-chloroethyl isopropyl carbonate (221.6 mg, 1.33 mmol) was then reacted with chiral 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-3-methoxybenzoic acid (150.3 mg, 244 μmol) in the presence of cesium carbonate (478 mg, 1.47 mmol) in dimethylformamide (5 mL) overnight to give, after flash chromatography purification (hexane/ethyl acetate, 80/20 to 20/80), 1-(isopropoxycarbonyloxy)ethyl 4-((2R,3S,4R,5S)-3-(3-chloro-2-fluorophenyl)-4-(4-chloro-2-fluorophenyl)-4-cyano-5-neopentylpyrrolidine-2-carboxamido)-3-methoxybenzoate (134.4 mg, 73% yield). MS (ES+) m/z calcd. for C37H40Cl2F2N3O7: [(M+H)+]: 746, found: 746

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2-propanol (2.66 mL, 34.97 mmol) and pyridine (3.39 mL, 41.96 mmol), pre-cooled in a dry-ice/acetone bath was slowly added 1-chloroethyl chloroformate. The resulting mixture was allowed to slowly warm to 25° C. overnight, with stirring. After concentration under reduced pressure the mixture was dissolved in ethyl acetate. The organic layer was washed with brine, dried over sodium sulfate, filtered and concentrated under reduced pressure to give 1-chloroethyl isopropyl carbonate as a pink/orange oil (5.11 g, 88% yield). After concentration under reduced pressure the mixture was dissolved in ethyl acetate The organic layer was washed with brine dried over sodium sulfate filtered concentrated under reduced pressure

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

Procedure: (2S,4S)-5-Biphenyl-4-yl-4-t-butoxycarbonylamino-2-hydroxymethyl-pentanoic acid (50 mg, 120 μmol, 1.0 eq.), DMA (1 mL), DIPEA (0.13 mL) and 1-chloroethyl isopropyl carbonate (83 mg, 0.5 mmol, 4.0 eq.) were combined. The reaction vessel was capped and microwaved at 80° C. for 2 hours. The mixture was dried under vacuum, dissolved in MeCN (2 mL), and combined with 4 M of HCl in dioxane (500 μL). The resulting mixture was stirred at room temperature for 30 minutes. The precipitate was filtered and discarded, and the filtrate containing the intermediate was concentrated down and submitted to the next step. 1,2,3-Triazole-4-carboxylic acid (14 mg, 120 μmol, 0.5 eq.) and HATU (48 mg, 120 μmol, 1.0 eq) were dissolved in DMF (1 mL) and the resulting solution was stirred for 5 minutes, followed by the addition of DIPEA (44 μL) and the intermediate from last step. The mixture was stirred for 5 minutes. The reaction was quenched with water and the product dried under vacuum. The product was then purified by preparative HPLC to yield the title compound (6 mg; purity 95%). MS m/z [M+H]+ calc'd for C27H32N4O7, 525.23. found 525.4. The reaction vessel was capped microwaved at 80° C. for 2 hours The mixture was dried under vacuum dissolved in MeCN (2 mL) The precipitate was filtered the filtrate containing the intermediate was concentrated down and the resulting solution was stirred for 5 minutes The mixture was stirred for 5 minutes The reaction was quenched with water the product dried under vacuum The product was then purified by preparative HPLC

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

Procedure: (2S,4S)-5-Biphenyl-4-yl-4-t-butoxycarbonylamino-2-hydroxymethyl-pentanoic acid (50 mg, 120 μmol, 1.0 eq.), DMA (1 mL), DIPEA (0.13 mL) and 1-chloroethyl isopropyl carbonate (83 mg, 0.5 mmol, 4.0 eq.) were combined. The reaction vessel was capped and microwaved at 80° C. for 2 hours. The mixture was dried under vacuum, dissolved in MeCN (2 mL), and combined with 4 M of HCl in dioxane (500 μL). The resulting mixture was stirred at room temperature for 30 minutes. The precipitate was filtered and discarded, and the filtrate containing the intermediate was concentrated down and submitted to the next step. 1,2,3-Triazole-4-carboxylic acid (14 mg, 120 μmol, 0.5 eq.) and HATU (48 mg, 120 μmol, 1.0 eq) were dissolved in DMF (1 mL) and the resulting solution was stirred for 5 minutes, followed by the addition of DIPEA (44 μL) and the intermediate from last step. The mixture was stirred for 5 minutes. The reaction was quenched with water and the product dried under vacuum. The product was then purified by preparative HPLC to yield the title compound (6 mg; purity 95%). MS m/z [M+H]+ calc'd for C27H32N4O7, 525.23. found 525.4. The reaction vessel was capped microwaved at 80° C. for 2 hours The mixture was dried under vacuum dissolved in MeCN (2 mL) The precipitate was filtered the filtrate containing the intermediate was concentrated down and the resulting solution was stirred for 5 minutes The mixture was stirred for 5 minutes The reaction was quenched with water the product dried under vacuum The product was then purified by preparative HPLC

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

Procedure: (2S,4S)-5-Biphenyl-4-yl-4-t-butoxycarbonylamino-2-hydroxymethyl-pentanoic acid (50 mg, 120 μmol, 1.0 eq.), DMA (1 mL), DIPEA (0.13 mL) and 1-chloroethyl isopropyl carbonate (83 mg, 0.5 mmol, 4.0 eq.) were combined. The reaction vessel was capped and microwaved at 80° C. for 2 hours. The mixture was dried under vacuum, dissolved in MeCN (2 mL), and combined with 4 M of HCl in dioxane (500 μL). The resulting mixture was stirred at room temperature for 30 minutes. The precipitate was filtered and discarded, and the filtrate containing the intermediate was concentrated down and submitted to the next step. 1,2,3-Triazole-4-carboxylic acid (14 mg, 120 μmol, 0.5 eq.) and HATU (48 mg, 120 μmol, 1.0 eq) were dissolved in DMF (1 mL) and the resulting solution was stirred for 5 minutes, followed by the addition of DIPEA (44 μL) and the intermediate from last step. The mixture was stirred for 5 minutes. The reaction was quenched with water and the product dried under vacuum. The product was then purified by preparative HPLC to yield the title compound (6 mg; purity 95%). MS m/z [M+H]+ calc'd for C27H32N4O7, 525.23. found 525.4. The reaction vessel was capped microwaved at 80° C. for 2 hours The mixture was dried under vacuum dissolved in MeCN (2 mL) The precipitate was filtered the filtrate containing the intermediate was concentrated down and the resulting solution was stirred for 5 minutes The mixture was stirred for 5 minutes The reaction was quenched with water the product dried under vacuum The product was then purified by preparative HPLC

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

Procedure: (R)-7-[3-tert-Butoxycarbonylamino-4-(2,4,5-trifluoro-phenyl)-butyryl]-3-trifluoromethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine-1-carboxylic acid 2a (0.275 g, 0.5 mmol) and 4 mL of N,N-dimethylformamide were added into the reaction tube. After stirring until 2a was dissolved, 1-chloroethyl isopropyl carbonate (0.1 g, 0.6 mmol), potassium iodide (0.0415 g, 0.25 mmol) and potassium carbonate (0.083 g, 0.6 mmol) were then added to the solution successively. Upon completion of the addition, the reaction tube was sealed up. The reaction mixture was reacted at 65° C. for 2 hours in an oil bath and monitored by thin layer chromatography until the disappearance of the starting materials, and then the oil bath was removed. After cooling to room temperature, 40 mL of water was added to the reaction tube. The reaction mixture was extracted with ethyl acetate (25 mL×3). Thin layer chromatography showed there was no product in the aqueous phase, and the organic phase was collected, then washed with water (20 mL×2), then the combined organic phase was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography to obtain the title compound (R)-7-[3-tert-butoxycarbonylamino-4-(2,4,5-trifluoro-phenyl)-butyryl]-3-trifluoromethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine-1-carboxylic acid 1-isopropoxycarbonyloxy-ethyl ester 37a (0.29 g, yield 85.3%) as a yellow solid. was dissolved Upon completion of the addition the reaction tube was sealed up The reaction mixture was reacted at 65° C. for 2 hours in an oil bath the oil bath was removed 40 mL of water was added to the reaction tube The reaction mixture was extracted with ethyl acetate (25 mL×3) the organic phase was collected washed with water (20 mL×2) the combined organic phase was dried over anhydrous magnesium sulfate filtered concentrated under reduced pressure The resulting residue was purified by silica gel column chromatography