p-sulfonic acid calix [4] arene: An efficient reusable organocatalyst for the synthesis of bis (indolyl) methanes derivatives in water and under solvent-free conditions
... is not expected to last more than 10 minutes. Comptes Rendus Chimie. Volume 16, Issue 2, February 2013, Pages 129–134. Cover image Cover image. Full paper/Mémoire. p-sulfonic acid calix[4]arene: An efficient reusable ...