Boron tribromide → HCID 22219609, compound

Participants

Reaction Steps

To a 1 M solution of BBr3 (1.1 L, 1.6 equiv.), cooled at 0° C. with an ice water bath, add 6-methoxy-3-(2,2,2-trifluoroacetyl)-2,3,4,5-tetrahydro-1H-benzo[d]azepine (187 g, 0.684 mol) in DCM (200 mL) over 1 hr, while maintaining the temperature between 0° C. and 10° C. Warm the reaction mixture to RT and stir until HPLC indicates completion of the reaction (about 2 h.). Cool the solution to 0° C. and transfer it via cannula into an ice water solution (1.2 L), thereby precipitating the product as a white solid. Add EtOAc (2 L) to dissolve most of the precipitate, separate the layers and concentrate the organic layer. Extract the aqueous layer three times with EtOAc (2×2 L, 1×1 L). Wash the combined organic layers with water (2 L), and then brine (2 L), dry (sodium sulfate) and concentrate to give the title compound as a light yellow solid (166.3 g, 94%). Use the product for the next step without further purification. Prepare an analytical sample utilizing silica gel chromatography, eluting with 40:60 diethyl ether:hexanes.

Provenance & Evidence