Oxonium, trimethyl-, tetrafluoroborate(1-) (1:1) → HCID 24944536, compound

Participants

Reaction Steps

To a solution of tert-butyl 2-[difluoro(phenyl)methyl]-4-oxo-3,4,5,6,8,9-hexahydro-7H-pyrimido[4,5-d]azepine-7-carboxylate of Preparation 8, Step A (535 mg, 1.37 mmol) was added trimethyloxonium tetrafluoroborate (3 eq, 606 mgs 4.10 mmol) and the reaction mixture was stirred overnight at room temperature, after which time an orange solid had precipitated. The reaction mixture was quenched with saturated NaHCO3 (aq) and stirred rapidly until a complete solution was attained. The organic layer was collected, dried over MgSO4, filtered and dried in vacuo to give a brown oil. This material was chromatographed on silica, eluting with ethyl acetate/10% methanol, then dichloromethane/methanol/ammonia, 95/5/0.5. The relevant fractions were combined and evaporated in vacuo to give a coloured oil (quantitative yield).

Provenance & Evidence