A dinuclear Cu(OAc)2-anchored SBA-15 silica was synthesized, confirmed and showed excellent catalytic activity for the azide–alkyne cycloaddition reaction in water.

Phenylsulfonic acid-functionalized SBA-15 silica was found to be an efficient heterogeneous acid catalyst in Bischler cyclization for the synthesis of indole-2-carboxylic esters. Under the optimized conditions, a wide range of substituted 4-nitrobenzyl 3-hydroxy-2-(N-methyl-N-arylamino)-2-enoates could be smoothly transformed to the corresponding 4-nitrobenzyl indole-2-carboxylates in excellent yields (87-99 %). Moreover, the catalyst could be conveniently recovered and reused at least four times without significant loss of catalytic activity. Graphical Abstract N R 1 R 2 COOPNB R 1 N R 2 HO (10-30 mol%) SBA-15-PhSO 3 H OPNB O PNB : 4-Nitro Benzyl 13 examples 87-99% yields