Preferential precipitation of C70 from a toluene solution of C60 and C70 was accomplished with p-trihalohomooxacalix[3]arenes (13·X·X·X) prepared by the reductive coupling of diformylphenols. Heavy halogens, Br and/or I, are essential at the para position of 13·X·X·X for obtaining good yields and selectivities. C70 with up to 92% purity was obtained after the preferential precipitation.
通过二
甲醛苯酚还原偶联制备的对三卤代氧杂
喹喔啉并[3]烯(13-X-X-X)可以从 C60 和 C70 的
甲苯溶液中优先析出 C70。要获得良好的产率和选择性,13-X-X-X 对位上的重卤素(Br 和/或 I)是必不可少的。经优先沉淀后,可获得纯度高达 92% 的 C70。