Sulfuryl chloride → 2-Amino-3-chloro-5-(trifluoromethoxy)benzoic acid

Participants

Reaction Steps

To a solution of 2-amino-5-trifluoromethoxybenzoic acid (49.0 g, 0.22 mol; see step (ii) above) in HOAc (1200 mL) was slowly added sulfuryl chloride (41.8 g, 0.31 mol). Gas evolution was observed. The resulting heterogeneous mixture was stirred at room temperature for 1 h. Additional HOAc (300 mL) was added to aid stirring, followed by sulfuryl chloride in 5 mL portions until the starting material was consumed based on TLC analysis. The reaction was concentrated in vacuo to give solids that were flushed on a rotary evaporator with EtOAc (2×) followed by Et2O (1×) to remove the HOAc. The resulting solids were further dried to give the HCl salt of the crude sub-title compound (60.5 g, 94%), which was used in the next step without further purification.

Provenance & Evidence