Regioselective O-Substitution of C-Undecylresorcin[4]arene

Selectively functionalized resorcinarenes were obtained by weak-base-promoted O-alkylation of C-undecylresorcin[4]arene 1. Tetrasubstituted derivatives with C₄-1,3,5,7, C_2v-1,2,5,6, C_s-1,2,4,7, and C_i-1,2,4,6 pattern were obtained in workable yields by using K₂CO₃ as the base in acetone at reflux. The good regioselectivity with respect to the statistical distribution was explained in terms of preferential formation of H-bonded monoanions. Heptaaroylated resorcin[4]arenes were also easily obtained by reaction of 1 with aroyl chlorides in pyridine.