Triethylamine → 7-Bromo-6-methoxy-1(2H)-isoquinolinone

Participants

Reaction Steps

A portion of the product from Step 1 [(2E)-3-(4-bromo-3-methoxyphenyl)acrylic acid](12.5 g, 48.6 mmol) was azeotroped with benzene and suspended in benzene (94 mL). Triethylamine (9.49 mL, 68.1 mmol) and diphenylphosphoryl azide (10.48 mL, 48.6 mmol) were added and the reaction mixture stirred at RT for 1 h. The mixture was filtered through a pad of silica and eluted with ˜1 L of toluene, the volatiles evaporated, the residue resuspended in diphenylmethane (94 mL) and the mixture heated to reflux for three hours (internal temperature 250° C.). The reaction mixture was allowed to cool to RT, stirred overnight, filtered and the solid washed with hexanes (100 mL) to give tan solid (7.4 g). LRMS ESI+ (M+H)+ 254.1.

Provenance & Evidence