10-Bromo-9-fluoro-2,3-diiodo-5,6-dihydrobenzo[f]imidazo[1,2-d][1,4]oxazepine → 10-Bromo-9-fluoro-2-iodo-5,6-dihydrobenzo[f]imidazo[1,2-d][1,4]oxazepine

Participants

Reaction Conditions

Reaction Steps

Into a 20-L 4-necked round-bottom flask purged and maintained with an inert atmosphere of nitrogen was placed a solution of 9-Bromo-8-fluoro-2,3-diiodo-4,5-dihydro-6-oxa-1,3a-diaza-benzo[e]azulene (886 g, 1.66 mol, 1.00 equiv) in tetrahydrofuran (7 L), followed by the addition of ethylmagnesium bromide (1987 mL, 1.20 equiv, 1 M) dropwise with stirring at −40° C. The resulting solution was stirred at room temperature for 30 min. This reaction was repeated for 2 times. The reaction was then quenched by the addition of 10 L of saturated aqueous NH4Cl and diluted with 24 L of tetrahydrofuran. The resulting solution was separated and the aqueous layer was extracted with 4×3 L of tetrahydrofuran. The organic layers were combined and concentrated under vacuum. The solids were collected by filtration, washed with 1)(2 L of EA and dried to afford 2100 g (crude) of 9-Bromo-8-fluoro-2-iodo-4,5-dihydro-6-oxa-1,3a-diaza-benzo[e]azulene as a brown solid.

Provenance & Evidence