Acetylimidazole diethyl acetal → HCID 68283491, compound

Participants

Reaction Conditions

Reaction Steps

1-(1,1-Diethoxyethyl)-1H-imidazole (7 g, 38.0 mmol) was dissolved in diethyl ether (100 ml) and cooled to −40° C. and n-BuLi (1.6M in hexane) (23.75 ml, 38.0 mmol) was added. The solution was stirred for 10 minutes and 7-bromo-4-fluoro-2-methoxy-9H-xanthen-9-one (Example 5, 6.14 g, 19.00 mmol) was added in one portion. The solution was stirred one hour at −40° C., then allowed to warm to RT for 15 minutes. The solution was quenched with 2 N HCl until at pH 1, stirred for 15 minutes, then made basic with concentrated sodium carbonate and stirred for 15 minutes. The product was collected by filtration. The filtrate was also extracted with EtOAc, the extracts were concentrated and combined with the material collected by filtration. The product was loaded onto silica and purified via silica gel column chromatography (RediSep 80 g column) using 10-50% 90/10/1 (DCM/MeOH/ammonia) in DCM to afford 7-bromo-4-fluoro-9-(1H-imidazol-2-yl)-2-methoxy-9H-xanthen-9-ol (3.4 g, 8.69 mmol) as an off white solid.

Provenance & Evidence