Thionyl Chloride → 5-Bromo-9-azatricyclo(8.1.1.0,2,7)dodeca-2,4,6-trien-8-one

Participants

Reaction Conditions

Reaction Steps

Into a 20-L 4-necked round-bottom flask was placed 6-Bromo-2,3-dihydro-1H-1,3-methano-naphthalen-4-one oxime (790 g, 3.13 mol, 1.00 equiv), 1,4-dioxane (7.5 L), followed by the addition of a solution of thionyl chloride (12000 g, 32.00 equiv) in 1,4-dioxane (7.5 L) dropwise with stirring at 25° C. The resulting solution was stirred at 65° C. for 6 h. This reaction was repeated for 2 more times. The resulting mixture was concentrated under vacuum, diluted with 10 L of DCM and then quenched by the addition of 8 L of water. The resulting solution was extracted with 2×10 L of dichloromethane and the organic layers were combined. The pH value of the solution was adjusted to 7 with sodium bicarbonate (sat.). The organic layer was dried over anhydrous sodium sulfated and concentrated under vacuum. The residue was diluted with 4 L of EA and stirred at reflux for 0.5 h. The solids were collected by filtration and washed with 2×500 mL, of EA. The filtrate was concentrated under vacuum. The residue was applied onto a silica gel column eluting with PE:EA (5:1-3:1). This solid was combined with the previous solids to afford 1749 g (74%) of 5-Bromo-9-aza-tricyclo[8.1.1.0[2,7]]dodeca-2,4,6-trien-8-one as an off-white solid.

Provenance & Evidence