Sodium Bicarbonate → racemic tert-butyl ((5RS,6RS)-5-(2-fluoro-5-nitrophenyl)-6-(2-hydroxyethyl)-2,2,5-trimethyl-1,1-dioxido-5,6-dihydro-2H-1,4-thiazin-3-yl)carbamate

Participants

Reaction Steps

A solution of tert-butyl ((5RS,6RS)-6-allyl-5-(2-fluoro-5-nitrophenyl)-2,2,5-trimethyl-1,1-dioxido-5,6-dihydro-2H-1,4-thiazin-3-yl)carbamate (120 mg, 0.256 mmol) in DCM (1.8 ml) and MeOH (0.6 ml) was cooled to −78° C., and sodium bicarbonate (42.9 mg, 0.511 mmol) was added and the mixture was ozonolyzed for 10 min. Oxygen was bubbled through the solution for 2 min, then solid sodium borohydride (14.5 mg, 0.383 mmol) was added to the mixture and the mixture was removed from the cooling bath and was allowed to reach RT and stirred for 30 min. The reaction was quenched with sat. solution of NH4Cl and extracted with EtOAc. The organic layer was washed with brine, dried over MgSO4 and concentrated to afford crude racemic tert-butyl ((5RS,6RS)-5-(2-fluoro-5-nitrophenyl)-6-(2-hydroxyethyl)-2,2,5-trimethyl-1,1-dioxido-5,6-dihydro-2H-1,4-thiazin-3-yl)carbamate (120 mg, 0.253 mmol, 99% yield) which was used without further purification.

Provenance & Evidence