tert-butyl (2S,5S)-5-[[tert-butyl(dimethyl)silyl]oxymethyl]-2-(hydroxymethyl)morpholine-4-carboxylate

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

Procedure: To a stirring solution of sodium hydride (0.257 g, 6.43 mmol) (pre-washed in hexanes) in DMF (15.30 mL) at 0° C., tert-butyl (2S,5S)-5-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-(hydroxymethyl)morpholine-4-carboxylate (Example 1, Step 5) (1.66 g, 4.59 mmol) in DMF (2 mL) was added dropwise. The resulting mixture was stirred at 0° C. for 1 hour. At this point, 1,2-difluoro-3-nitrobenzene (0.494 mL, 4.50 mmol) in 0.5 mL of DMF was added dropwise and the final solution was slowly warmed toward room temperature and stirred for 1 hour. Complete by LC/MS at this time. The contents were quenched by adding saturated aqueous sodium bicarbonate and then extracted between water and EtOAc (3×75 mL). The organic layer was dried over MgSO4, filtered and concentrated. Purification on silica gel (120 g) eluting with a gradient of 0-60% EtOAc/hexanes afforded the title compound (1.68 g, 3.36 mmol, 73% yield) as a yellow oil, MS (ESI): m/z=401.11 (M+H-boc). stirred for 1 hour The contents were quenched by adding saturated aqueous sodium bicarbonate extracted between water and EtOAc (3×75 mL) The organic layer was dried over MgSO4 filtered concentrated Purification on silica gel (120 g) eluting with a gradient of 0-60% EtOAc/hexanes

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of oxalyl chloride (2 eq) in DCM (0.3 M) at −78° C. was added a solution of DMSO (5 eq) in DCM (0.5M). The reaction mixture was stirred at −78° C. for 30 min. A solution of tert-butyl (2S,5S)-5-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-(hydroxymethyl)morpholine-4-carboxylate (1 eq) in CH2Cl2 (0.2M) was added dropwise and stirred at −40° C. for 1.5 hours. It was then cooled to −78° C. and triethylamine (7 eq) was added and the reaction mixture was stirred at 0° C. for 1 h. Water was added and the reaction mixture was warmed to rt for 30 min. The mixture was diluted with CH2Cl2, the organic layer was washed with water and brine, dried over Na2SO4, filtered and concentrated. The crude product was used as such for the next step. stirred at −40° C. for 1.5 hours It was then cooled to −78° C. the reaction mixture was stirred at 0° C. for 1 h the reaction mixture was warmed to rt for 30 min the organic layer was washed with water and brine dried over Na2SO4 filtered concentrated

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of oxalyl chloride (2 eq) in DCM (0.3 M) at −78° C. was added a solution of DMSO (5 eq) in DCM (0.5M). The reaction mixture was stirred at −78° C. for 30 min. A solution of tert-butyl (2S,5S)-5-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-(hydroxymethyl)morpholine-4-carboxylate (1 eq) in CH2Cl2 (0.2M) was added dropwise and stirred at −40° C. for 1.5 hours. It was then cooled to −78° C. and triethylamine (7 eq) was added and the reaction mixture was stirred at 0° C. for 1 h. Water was added and the reaction mixture was warmed to rt for 30 min. The mixture was diluted with CH2Cl2, the organic layer was washed with water and brine, dried over Na2SO4, filtered and concentrated. The crude product was used as such for the next step. stirred at −40° C. for 1.5 hours It was then cooled to −78° C. the reaction mixture was stirred at 0° C. for 1 h the reaction mixture was warmed to rt for 30 min the organic layer was washed with water and brine dried over Na2SO4 filtered concentrated

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

Procedure: To a stirring solution of sodium hydride (0.257 g, 6.43 mmol) (pre-washed in hexanes) in DMF (15.30 mL) at 0° C., tert-butyl (2S,5S)-5-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-(hydroxymethyl)morpholine-4-carboxylate (Example 1, Step 5) (1.66 g, 4.59 mmol) in DMF (2 mL) was added dropwise. The resulting mixture was stirred at 0° C. for 1 hour. At this point, 1,2-difluoro-3-nitrobenzene (0.494 mL, 4.50 mmol) in 0.5 mL of DMF was added dropwise and the final solution was slowly warmed toward room temperature and stirred for 1 hour. Complete by LC/MS at this time. The contents were quenched by adding saturated aqueous sodium bicarbonate and then extracted between water and EtOAc (3×75 mL). The organic layer was dried over MgSO4, filtered and concentrated. Purification on silica gel (120 g) eluting with a gradient of 0-60% EtOAc/hexanes afforded the title compound (1.68 g, 3.36 mmol, 73% yield) as a yellow oil, MS (ESI): m/z=401.11 (M+H-boc). stirred for 1 hour The contents were quenched by adding saturated aqueous sodium bicarbonate extracted between water and EtOAc (3×75 mL) The organic layer was dried over MgSO4 filtered concentrated Purification on silica gel (120 g) eluting with a gradient of 0-60% EtOAc/hexanes

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of oxalyl chloride (2 eq) in DCM (0.3 M) at −78° C. was added a solution of DMSO (5 eq) in DCM (0.5M). The reaction mixture was stirred at −78° C. for 30 min. A solution of tert-butyl (2S,5S)-5-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-(hydroxymethyl)morpholine-4-carboxylate (1 eq) in CH2Cl2 (0.2M) was added dropwise and stirred at −40° C. for 1.5 hours. It was then cooled to −78° C. and triethylamine (7 eq) was added and the reaction mixture was stirred at 0° C. for 1 h. Water was added and the reaction mixture was warmed to rt for 30 min. The mixture was diluted with CH2Cl2, the organic layer was washed with water and brine, dried over Na2SO4, filtered and concentrated. The crude product was used as such for the next step. stirred at −40° C. for 1.5 hours It was then cooled to −78° C. the reaction mixture was stirred at 0° C. for 1 h the reaction mixture was warmed to rt for 30 min the organic layer was washed with water and brine dried over Na2SO4 filtered concentrated