Diethyl chlorophosphate → HCID 58557150, compound

Participants

Reaction Steps

To a solution of 1-tert-butyl 3-ethyl 4-oxopiperidine-1,3-dicarboxylate (11.50 g, 42.4 mmol, ASDI) in MTBE (500 mL) at about −78° C. was added NaHMDS (1 M in THF, 53.0 mL, 53.0 mmol). After about 1 h, diethyl phosphorochloridate (7.62 mL, 53.0 mmol) was added to the reaction mixture. After about 30 min, the reaction mixture was allowed to warm to ambient temperature and stirred for about 16 h. The reaction mixture was partitioned between saturated aqueous NH4Cl (100 mL) and EtOAc (50 mL). The layers were separated. The aqueous layer was further extracted with EtOAc (2×50 mL). The combined organic layers were dried over anhydrous Na2SO4, filtered, and concd under reduced pressure. The crude material was purified by silica gel chromatography eluting with a gradient of 0-100% EtOAc in heptane to yield 1-tert-butyl 3-ethyl 4-(diethoxyphosphoryloxy)-5,6-dihydropyridine-1,3(2H)-dicarboxylate (8.55 g, 49%) as a yellow oil: LC/MS (Table 1, Method b) Rt=2.35 min; MS m/z: 408 (M+H)+.

Provenance & Evidence