HCID 66666120, compound → HCID 66666069, compound

Participants

Reaction Steps

A cooled (0° C.) mixture of 6,7-diphenyl-1,8-naphthyridine 1-oxide and 2,3-diphenyl-1,8-naphthyridine 1-oxide (Intermediates C) (1 g, 3.35 mmol) in dry THF (10 ml) under an atmosphere of N2 was treated dropwise with methylmagnesium chloride (1.676 ml, 5.03 mmol). The resulting mixture was stirred at room temperature for 45 minutes and then partitioned between EtOAc and water. The aqueous portion was extracted with EtOAc (2×100 ml) and the combined organic extracts were washed with brine, dried over MgSO4, filtered and concentrated in vacuo. The crude residue was dissolved in acetic anhydride (5 ml) and heated at 120° C. for 10 mins using microwave radiation. The resulting mixture was partitioned between DCM (150 ml) and water. The organic portion was washed with brine, dried over MgSO4, filtered and concentrated in vacuo. The crude product was loaded onto a Isolute™ SCX-2 cartridge and eluted with MeOH followed by 2M NH3 in MeOH. The methanolic ammonia fractions were concentrated in vacuo to afford a brown oil which was purified by chromatography on silica eluting with 0-50% EtOAc in iso-hexane to afford the title product;

Provenance & Evidence