A practical oxidative homo‐ and heterocoupling of terminal alkynes was achieved in CH2Cl2 at 25 °C by using a 3‐(2‐aminoethylamino)propyl‐functionalized MCM‐41‐immobilized copper(I) complex (MCM‐41–2N‐CuI, 1 mol‐%) as the catalyst, piperidine (0.1 or 3 equiv.) as the base, and air as the environmentally friendly co‐oxidant, yielding a variety of symmetrical and unsymmetrical 1,4‐disubstituted 1,3‐diynes in good to excellent yields. This heterogeneous copper catalyst showed a higher catalytic activity than CuI and can be recovered and recycled by a simple filtration of the reaction mixture and used for at least 10 consecutive runs without any decrease in activity.

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The heterogeneous cascade three-component reaction of amines, carbon disulfide (CS 2 ) and 2-iodoanilines was achieved in dimethylformamide (DMF) at 110 8C in the presence of 10 mol% of 3-(2aminoethylamino)propyl-functionalized MCM-41-immobilized copper complex [MCM-41-2N-CuCl] using potassium carbonate (K 2 CO 3 ) as base, yielding a variety of 2-aminobenzothiazoles in good to excellent yields. This heterogeneous copper catalyst influences the selectivity of the reaction and can be recovered and recycled by a simple filtration of the reaction solution and used for at least 10 consecutive trials without any decreases in activity.

Heterogeneous C-S coupling reaction of thiols with polychloroalkanes or alkyl halides was achieved at 30 or 80°C in the presence of 5 mol% of an MCM-41-immobilized bidentate phosphine rhodium complex (MCM-41-2P-RhCl(PPh 3 )) and triethylamine, yielding a variety of formaldehyde dithioacetals, ethylenedithioethers and unsymmetric thioethers in good to excellent yields. This heterogeneous rhodium catalyst can be easily recovered and recycled by simple filtration of the reaction solution and used for at least 10 consecutive trials without significant loss of activity.

The heterogeneous cascade reaction of 2-halobenzoic acids and amidines was achieved in DMF at 60 C in the presence of 10 mol% of MCM-41-immobilized tridentate nitrogen copper(I) complex [MCM-41-3N-CuI] using Cs 2 CO 3 as base, yielding a variety of quinazolinone derivatives in good to excellent yields. This heterogeneous copper catalyst can be easily prepared from commercially available and inexpensive reagents, and recovered by a simple filtration of the reaction solution and reused for at least 10 times without any decreases in activity.