反应详情

Preparation of bis(4-t-butylphenyl)iodonium 9,10-diethoxyanthracene-2-sulfonate according to Formula 2 above wherein R3 and R4 are both t-butyl and OR5 and OR6 are both ethoxy is as follows. A slurry of 399 g potassium periodate (1.86 M) was prepared in a pre-made solution of 761 g (705 mL, 7.45 M) acetic anhydride in 500 g (577 mL, 3.725 M) of t-butylbenzene using mechanical stirring. While cooling with ice bath, 402 g (4.1 M) of concentrated H2SO4 was added slowly, maintaining the temperature at 25±5° C. (approximately 2 hours). The reaction was allowed to stir overnight, allowing ice to melt in bath. The next day the reaction was re-cooled to 0-10° C. and a total of 1.25 L H2O added. Initially the reaction was very exothermic, but as the addition proceeded the water was added more rapidly. 252 mL of ammonium hydroxide was added next, followed by 1.5 L dichloromethane. The water layer was discarded, and the dichloromethane layer washed several times with water. The dichloromethane layer was dried with magnesium sulfate and filtered, then evaporated to a low volume on a rotary evaporate to induce crystallization. The solid was filtered and rinsed with toluene and sucked dry. The residue was recrystallized from IPA to yield 243 g of a white solid of bis(4-t-butylphenyl)iodonium acetate. The bis(4-t-butylphenyl)iodonium acetate may then be combined under suitable conditions known in the art with 9,10-diethoxyanthracene-2-sulfonic acid, potassium salt to yield bis(4-t-butylphenyl)iodonium 9,10-diethoxyanthracene-2-sulfonate. Alternatively, 9,10-dimethoxyanthracene-2-sulfonic acid, potassium salt may be used to yield a sulfonium salt according to Formula 2 wherein OR5 and OR6 are both methoxy.