4-Nitrophenyl chloroformate → (+/-)-4-Oxo-2-pyrimidin-4-yl-4,6,7,8,9,10-hexahydro-pyrimido[1,2-a]azepine-10-carboxylic acid (4-nitro-phenyl) ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 0.500 g (2.06 mmol) of 2-pyrimidin-4-yl-7,8,9,10-tetrahydro-6H-pyrimido[1,2-a]azepin-4-one (step 6.1 of example 6) in dry tetrahydrofuran (20 mL) under argon at −40° C. was added 2.27 mL (2.27 mmol) of lithium bis(trimethylsilyl)amide (1M in tetrahydrofuran). The solution was stirred at −50° C. for 10 min and 1.04 g (5.16 mmol) of 4-nitrophenyl chloroformate diluted in 3 ml of dry tetrahydrofuran was added. The mixture was quenched with the addition of a saturated solution of ammonium chloride and extracted with dichloromethane. The organic phase was dried over sodium sulfate and concentrated. The residue was used as such for the next step.

Provenance & Evidence