Sodium Thiosulfate → benzhydryl (6R,7R)-3-(chloromethyl)-7-[[(2Z)-2-[2-methyl-1-[(2-methylpropan-2-yl)oxy]-1-oxopropan-2-yl]oxyimino-2-[2-[(2-methylpropan-2-yl)oxycarbonylamino]-1,3-thiazol-4-yl]acetyl]amino]-5,8-dioxo-5lambda4-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

To a solution of (6R,7R)-benzhydryl 7-((Z)-2-(((1-(tert-butoxy)-2-methyl-1-oxopropan-2-yl)oxy)imino)-2-(2-((tert-butoxycarbonyl)amino)thiazol-4-yl)acetamido)-3-(chloromethyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate (3 g, 3.63 mmol) in dichloromethane (DCM) (100 mL) at −40° C. was added dropwise a solution of 3-chlorobenzoperoxoic acid (0.976 g, 4.36 mmol) in dichloromethane 20 mL) over 1 min. The mixture was stirred at the same temperature over 30 min. LCMS indicated completion of the reaction. Dichloromethane (60 mL) was added and the mixture was treated with 15% aqueous sodium thiosulfate (40 mL). The organic solution was separated and washed with 5% sodium bicarbonate (80 mL), brine (80 mL), dried over sodium sulfate, and concentrated. The residue was purified by ISCO automated silica gel chromatography (120 g column, 0-50% ethyl acetate/hexanes) to afford (6R,7R)-benzhydryl 7-((Z)-2-(((1-(tert-butoxy)-2-methyl-1-oxopropan-2-yl)oxy)imino)-2-(2-((tert-butoxycarbonyl)amino)thiazol-4-yl)acetamido)-3-(chloromethyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate 5-oxide (2.44 g, 2.90 mmol, 53.2% yield) as a white solid. LCMS: (M+H)+: 842.2.

Provenance & Evidence