1314582-88-1Relevant articles and documents
Regioselective upper rim substitution of calix[4]arenes
Hudecek, Oldrich,Curinova, Petra,Budka, Jan,Lhoták, Pavel
, p. 5213 - 5218 (2011/07/31)
The electrophilic substitution of 25,27-dipropoxy-26,28-dinosyloxycalix[4] arene leads exclusively to the para-substitution of the alkylated phenol rings, while in the next step, the protecting nosyl group can be easily removed using a basic hydrolysis. The overall process yields dialkoxycalix[4]arenes with the substitution on the alkylated rings - the substitution pattern, which is complementary to the common dialkoxycalix[4]arenes with substituted nonalkylated phenolic units. The usefulness of this protection/deprotection procedure was documented by the synthesis of novel type of calixarene dipropoxy derivatives, and by the preparation of a novel anion receptor based on this substitution pattern.