Thes ynthesis of molecular-level artificial switchable catalysts, of which activity in different chemical processes can be switchedb yc ontrolling different stimuli, has provided an ew paradigm to perform mechanical tasks and measurable work. In this work, to obtain highly effective and regioselective artificials witchable catalysts, ah ierarchical anion-pillaredf ramework {(H 3 O)[Cu(CPCDC)(4,4'-bpy)]} n (1; H 3 CPCDC = 9-(4-carboxyphenyl)-9H-carbazole-3,6-dicarboxylic acid, 4,4'-bpy = 4,4'-bipyridine),i ncluding free [H 3 O] + ions as guest molecules, was constructed. Upon dissolve-exchangecrystallization behavior,f ascinating reversible structural transformationsp roceeded between anion framework 1 and neutral 2D stair-stepping framework {[Cu(CPCDC)(4,4'-bpe)]} n (2;4 ,4'-bpe = 4,4'-vinylenedipyridine). Moreover,f rameworks 1 and 2 can act as heterogeneousa rtificial switchable catalysts to selectively promotet he direct cyanation reactiono f terminal alkynes and azobisisobutyronitrile. The results indicated that 1 and 2 exhibited excellent selectivity to generate vinyl isobutyronitrile skeletons or propiolonitrile frameworks, respectively,a su nique products.F urthermore, indicating paper,G C-MS, energy-dispersive X-ray spectroscopy,a nd Xray photoelectrons pectroscopy analysis demonstrated that the reversible structural transformations endowed 1 and 2 with well-definedp latforms to stabilize the isobutyronitrile and CN sources through the different catalytic pathways.[a] Dr.