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Combining strain-promoted azide–alkyne cycloaddition (SPAAC) and inorganic click (iClick) reactivity provides access to metal 1,2,3-triazolates. Experimental and computational insights demonstrate that iClick reactivity of the tested metal azides (LM-N 3 , M = Au, W, Re, Ru and Pt) depends on the accessibility of the azide functionality rather than electronic effects imparted by the metal. SPAAC iClick reactivity with cyclooctyne is observed when the azide functionality is sterically unencumbered, e.g. [Au(N 3 )(PPh 3 )] (Au–N3), [W(η 3 -allyl)(N 3 )(bpy)(CO) 2 ] (W–N3), and [Re(N 3 )(bpy)(CO) 3 ] [bpy = 2,2′-bipyridine] (Re–N3). Increased steric bulk and/or preequilibria with high activation barriers prevent SPAAC iClick reactivity for the complexes [Ru(N 3 )(Tp)(PPh 3 ) 2 ] [Tp = tris(pyrazolyl)borate] (Ru–N3), [Pt(N 3 )(CH 3 )(P i Pr 3 ) 2 ] [ i Pr = isopropyl] (Pt(II)–N3), and [Pt(N 3 )(CH 3 ) 3 ] 4 ((PtN3)4). Based on these computational insights, the SPAAC iClick reactivity of [Pt(N 3 )(CH 3 ) 3 (P(CH 3 ) 3 ) 2 ] (Pt(IV)–N3) was successfully predicted. 

Systematic investigations were performed with various substituted groups at C8 purine and ribose. A series of isoG analogs, C8-phenyl substituted isoG were synthesized and applied for Cs + coordination. The structural proximity between purine and ribose limited pentaplex formation for C8-phenyl substituted isoG derivatives. Based on this observation, deoxy isoG derivative with modification on ribose ( tert -butyldimethylsilyl ether) was applied to assemble with the Cs + cation. Critical solvent (CDCl 3 and CD 3 CN) and anion (BPh 4 − , BARF − , and PF 6 − ) effects were revealed, leading to the controllable formation of various stable isoG pentaplexes, including singly charged decamer, doubly charged decamer, and 15-mer, etc. Finally, the X-ray crystal structure of [isoG 20 Cs 3 ] 3+ (BARF − ) 3 was successfully obtained, which is the first example of multiple-layer deoxy isoG binding with the Cs + cation, providing solid evidence of this new isoG ionophore beyond two-layer sandwich self-assembly.