Diphosgene → (2S,5R)-tert-butyl 5-(benzyloxy(chlorocarbonyl)amino)-2-(1,2,4-thiadiazol-5-yl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

Diphosgene (360 mg, 1.8 mmol) was added to a solution of (2S,5R)-tert-butyl 5-(benzyloxyamino)-2-(1,2,4-thiadiazol-5-yl)piperidine-1-carboxylate (468 mg, 1.2 mmol) in dry DCM (20 mL) at 0° C. followed by addition of TEA (360 mg, 3.6 mmol). The mixture was stirred at 0° C. for 2 hrs and then quenched with saturated NaHCO3 (20 mL). The reaction mixture was then extracted with DCM (3×) and the combined organic layer was dried over Na2SO4 and concentrated to afford (2S,5R)-tert-butyl 5-(benzyloxy(chlorocarbonyl)amino)-2-(1,2,4-thiadiazol-5-yl)piperidine-1-carboxylate, which was directly used in the next step. ESI-MS (EI+, m/z): 445 [M+H]+.

Provenance & Evidence