tert-butyl N-(4-hydrazinyl-4-oxobutyl)carbamate

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

Procedure: To a 0° C. solution of (2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carboxylic acid (12.0 g, 43.5 mmol) and tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (10.5 g, 47.8 mmol) in CH2Cl2 (360 mL) was added HATU (19.6 g, 52.2 mmol) and DIPEA (16.6 g, 130.5 mmol). The mixture was allowed to warm to rt, was stirred at rt for 12 hrs then diluted with CH2Cl2 (300 mL), washed with water (2×) and saturated sodium chloride (2×), dried over Na2SO4, and concentrated. The residue was purified by silica gel column chromatography (gradient elution 50-80% EtOAc/petroleum ether) to afford tert-butyl 4-(2-((2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carbonyl)hydrazinyl)-4-oxobutylcarbamate (19.3 g, 93%) as a white solid. ESI-MS (EI+, m/z): 476 [M+H]+. washed with water (2×) and saturated sodium chloride (2×) dried over Na2SO4 concentrated The residue was purified by silica gel column chromatography (gradient elution 50-80% EtOAc/petroleum ether)

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

Procedure: To a solution of methyl 4-(tert-butoxycarbonylamino)butanoate (21.0 g, 96.8 mmol) in MeOH (180 mL) was added NH2NH2.H2O (28.0 g, 483 mmol) at rt. The mixture was stirred at 65° C. for 12 hrs then concentrated under reduced pressure. The crude material was dissolved in DCM (400 mL). The organic layer was washed with water (2×), and saturated sodium chloride (2×), dried over Na2SO4, and concentrated to afford tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (18.9 g, 90%) as a white solid. ESI-MS (EI+, m/z): 240 [M+Na]+. then concentrated under reduced pressure The crude material was dissolved in DCM (400 mL) The organic layer was washed with water (2×), and saturated sodium chloride (2×) dried over Na2SO4 concentrated

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

Procedure: To a 0° C. solution of (2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carboxylic acid (12.0 g, 43.5 mmol) and tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (10.5 g, 47.8 mmol) in CH2Cl2 (360 mL) was added HATU (19.6 g, 52.2 mmol) and DIPEA (16.6 g, 130.5 mmol). The mixture was allowed to warm to rt, was stirred at rt for 12 hrs then diluted with CH2Cl2 (300 mL), washed with water (2×) and saturated sodium chloride (2×), dried over Na2SO4, and concentrated. The residue was purified by silica gel column chromatography (gradient elution 50˜80% EtOAc/petroleum ether) to afford tert-butyl 4-(2-((2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carbonyl)hydrazinyl)-4-oxobutylcarbamate (19.3 g, 93%) as a white solid. ESI-MS (EI+, m/z): 476 [M+H]+. washed with water (2×) and saturated sodium chloride (2×) dried over Na2SO4 concentrated The residue was purified by silica gel column chromatography (gradient elution 50˜80% EtOAc/petroleum ether)

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

Procedure: To a solution of methyl 4-(tert-butoxycarbonylamino)butanoate (21.0 g, 96.8 mmol) in MeOH (180 mL) was added NH2NH2.H2O (28.0 g, 483 mmol) at rt. The mixture was stirred at 65° C. for 12 hrs then concentrated under reduced pressure. The crude material was dissolved in DCM (400 mL). The organic layer was washed with water (2×), and saturated sodium chloride (2×), dried over Na2SO4, and concentrated to afford tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (18.9 g, 90%) as a white solid. ESI-MS (EI+, m/z): 240 [M+Na]+. then concentrated under reduced pressure The crude material was dissolved in DCM (400 mL) The organic layer was washed with water (2×), and saturated sodium chloride (2×) dried over Na2SO4 concentrated

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

Procedure: To a 0° C. solution of (2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carboxylic acid (12.0 g, 43.5 mmol) and tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (10.5 g, 47.8 mmol) in CH2Cl2 (360 mL) was added HATU (19.6 g, 52.2 mmol) and DIPEA (16.6 g, 130.5 mmol). The mixture was allowed to warm to rt, was stirred at rt for 12 hrs then diluted with CH2Cl2 (300 mL), washed with water (2×) and saturated sodium chloride (2×), dried over Na2SO4, and concentrated. The residue was purified by silica gel column chromatography (gradient elution 50˜80% EtOAc/petroleum ether) to afford tert-butyl 4-(2-((2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carbonyl)hydrazinyl)-4-oxobutylcarbamate (19.3 g, 93%) as a white solid. ESI-MS (EI+, m/z): 476 [M+H]+. washed with water (2×) and saturated sodium chloride (2×) dried over Na2SO4 concentrated The residue was purified by silica gel column chromatography (gradient elution 50˜80% EtOAc/petroleum ether)

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

Procedure: To a solution of methyl 4-(tert-butoxycarbonylamino)butanoate (21.0 g, 96.8 mmol) in MeOH (180 mL) was added NH2NH2.H2O (28.0 g, 483 mmol) at rt. The mixture was stirred at 65° C. for 12 hrs then concentrated under reduced pressure. The crude material was dissolved in DCM (400 mL). The organic layer was washed with water (2×), and saturated sodium chloride (2×), dried over Na2SO4, and concentrated to afford tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (18.9 g, 90%) as a white solid. ESI-MS (EI+, m/z): 240 [M+Na]+. then concentrated under reduced pressure The crude material was dissolved in DCM (400 mL) The organic layer was washed with water (2×), and saturated sodium chloride (2×) dried over Na2SO4 concentrated

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

Procedure: To a 0° C. solution of (2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carboxylic acid (12.0 g, 43.5 mmol) and tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (10.5 g, 47.8 mmol) in CH2Cl2 (360 mL) was added HATU (19.6 g, 52.2 mmol) and DIPEA (16.6 g, 130.5 mmol). The mixture was allowed to warm to rt, was stirred at rt for 12 hrs then diluted with CH2Cl2 (300 mL), washed with water (2×) and saturated sodium chloride (2×), dried over Na2SO4, and concentrated. The residue was purified by silica gel column chromatography (gradient elution 50˜80% EtOAc/petroleum ether) to afford tert-butyl 4-(2-((2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carbonyl)hydrazinyl)-4-oxobutylcarbamate (19.3 g, 93%) as a white solid. ESI-MS (EI+, m/z): 476 [M+H]+. washed with water (2×) and saturated sodium chloride (2×) dried over Na2SO4 concentrated The residue was purified by silica gel column chromatography (gradient elution 50˜80% EtOAc/petroleum ether)

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

Procedure: To a solution of methyl 4-(tert-butoxycarbonylamino)butanoate (21.0 g, 96.8 mmol) in MeOH (180 mL) was added NH2NH2.H2O (28.0 g, 483 mmol) at rt. The mixture was stirred at 65° C. for 12 hrs then concentrated under reduced pressure. The crude material was dissolved in DCM (400 mL). The organic layer was washed with water (2×), and saturated sodium chloride (2×), dried over Na2SO4, and concentrated to afford tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (18.9 g, 90%) as a white solid. ESI-MS (EI+, m/z): 240 [M+Na]+. then concentrated under reduced pressure The crude material was dissolved in DCM (400 mL) The organic layer was washed with water (2×), and saturated sodium chloride (2×) dried over Na2SO4 concentrated

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

Procedure: To a 0° C. solution of (2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carboxylic acid (12.0 g, 43.5 mmol) and tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (10.5 g, 47.8 mmol) in CH2Cl2 (360 mL) was added HATU (19.6 g, 52.2 mmol) and DIPEA (16.6 g, 130.5 mmol). The mixture was allowed to warm to rt, was stirred at rt for 12 hrs then diluted with CH2Cl2 (300 mL), washed with water (2×) and saturated sodium chloride (2×), dried over Na2SO4, and concentrated. The residue was purified by silica gel column chromatography (gradient elution 50-80% EtOAc/petroleum ether) to afford tert-butyl 4-(2-((2S,5R)-6-(benzyloxy)-7-oxo-1,6-diaza-bicyclo[3.2.1]octane-2-carbonyl)hydrazinyl)-4-oxobutylcarbamate (19.3 g, 93%) as a white solid. ESI-MS (EI+, m/z): 476 [M+H]+. washed with water (2×) and saturated sodium chloride (2×) dried over Na2SO4 concentrated The residue was purified by silica gel column chromatography (gradient elution 50-80% EtOAc/petroleum ether)

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

Procedure: To a solution of methyl 4-(tert-butoxycarbonylamino)butanoate (21.0 g, 96.8 mmol) in MeOH (180 mL) was added NH2NH2.H2O (28.0 g, 483 mmol) at rt. The mixture was stirred at 65° C. for 12 hrs then concentrated under reduced pressure. The crude material was dissolved in DCM (400 mL). The organic layer was washed with water (2×), and saturated sodium chloride (2×), dried over Na2SO4, and concentrated to afford tert-butyl 4-hydrazinyl-4-oxobutylcarbamate (18.9 g, 90%) as a white solid. ESI-MS (EI+, m/z): 240 [M+Na]+. then concentrated under reduced pressure The crude material was dissolved in DCM (400 mL) The organic layer was washed with water (2×), and saturated sodium chloride (2×) dried over Na2SO4 concentrated