Benzenesulfonyl chloride → [(2S)-3,8-dioxo-1,2-dihydro-3H,8H-2a,5,8a-triazaacenaphthylen-2-yl]methyl benzenesulfonate

Participants

Reaction Conditions

Reaction Steps

To the suspension of (2S)-2-(hydroxymethyl)-1,2-dihydro-3H,8H-2a,5,8a-triazaacenaphthylene-3,8-dione (26.5 g, 121 mmol) in DCM (320 ml) was added benzenesulfonyl chloride (23.38 ml, 181 mmol) followed by Et3N (39.6 ml, 284 mmol). The reaction mixture was heated at gentle reflux at 42° C. for 2 h. Then, the reaction was cooled to 5° C. and 2-(dimethylamino)ethanol (7.30 ml, 72.5 mmol) was added dropwise. The crude was stirred at room temperature for 30 min and TBME (600 ml) was added. The obtained solid was filtered. The resulting solid was suspended in 100 ml 1N HCl and washed with water and TBME, dried to give [(2S)-3,8-dioxo-1,2-dihydro-3H,8H-2a,5,8a-triazaacenaphthylen-2-yl]methyl benzenesulfonate (37.04 g, 85%) as a cream solid.

Provenance & Evidence