​The synthesis, characterization, sulfonation, and catalytic performance of two new porous aromatic frameworks are presented. The polymers, which were obtained by the Suzuki–Miyaura cross-coupling of the commercially available precursors 1,3,5-tris(4-bromophenyl)benzene or tris(4-bromophenyl)amine and benzene-1 4-diboronic acid, only contain aromatic sp2 C−C and C−N bonds, display excellent thermal and chemical stability, and allow for post-synthetic functionalization under very harsh reaction conditions. Upon post-synthetic treatment at 160 °C in 98 wt % sulfuric acid, approximately 65 % of the benzene rings in the polymers were sulfonated. The materials were characterized by solid-state NMR spectroscopy, X-ray photoelectron spectroscopy, FTIR spectroscopy, and textural analysis. The sulfonated materials display an excellent catalytic performance in the acid-catalyzed esterification of n-butanol and acetic acid and have a similar or even superior performance to that of state-of-the-art Amberlyst-15 over multiple catalytic cycles.