Acetone → 3-Ethyl-2-{(4-methyl-2H-chromen-2-ylidene)methyl}-benzothiazolium perchlorate

Participants

Reaction Conditions

Reaction Steps

17.5 g of 3-ethyl-2-methylbenzothiazolium-p-toluenesulfonate and 8.8 g of 4-methylcoumarin-2-thione were reacted under heat at 150° C. for 15 hours, and 20 ml of methanol and 40 ml of acetone were then added to the reaction mixture in the order listed to obtaina uniform solution. After cooling to room temperature, 15.7 g of 60%-perchloric acid was added thereto and stirred at room temperature, whereby crystals precipitated out. The crystals formed were filtered out and washed with a small amount of acetone, and thereafter the crystals were placed in a mixed solvent comprising 20 ml of methanol and 40 ml of acetone at room temperature and stirred for 30 minutes. Then the crystals were again separated by filtration and washed with acetone, to finally obtain 8.5 g of the desired perchlorate product. Yield: 40%. Appearance: brown crystal. M.p.: above 280° C. (decomposition).

Provenance & Evidence