Toluene → p-Toluenesulfonic acid

Participants

Reaction Steps

In a round-bottomed flask (25 cm3) equipped with a magnetic stirrer flea and stopper, 1-decyl-3-methylimidazolium trifluoromethanesulfonate (0.97 g, 2.5 mmol) and toluene (0.46g, 5.0 mmol) were added. Sulfur trioxide (0.44g, 5.5 mmol) was cautiously added (carried out in a dry box) and the mixture stirred for 1 hour. A crude sample was taken from the flask and analysed by NMR (CDCl3, 300 MHz). This showed that the reaction was complete and gave 77% of p-toluenesulfonic acid and 22% o-toluenesulfonic acid. The products were isolated from the ionic liquid by Kugelrohr distillation at 1 mmHg. This gave colourless solid (bp=200° C. at 1 mmHg). The structures were confirmed by NMR analysis and were in accordance with authentic material.

Provenance & Evidence