Template‐assisted formation of multicomponent Pd
6 coordination prisms and formation of their self‐templated triply interlocked Pd
12 analogues in the absence of an external template have been established in a single step through Pd? N/Pd? O coordination. Treatment of
cis‐[Pd(en)(NO
3)
2] with K
3tma and linear pillar 4,4′‐bpy (en=ethylenediamine, H
3tma=benzene‐1,3,5‐tricarboxylic acid, 4,4′‐bpy=4,4′‐bipyridine) gave intercalated coordination cage [{Pd(en)}
6(bpy)
3(tma)
2]
2[NO
3]
12 ( 1 ) exclusively, whereas the same reaction in the presence of H
3tma as an aromatic guest gave a H
3tma‐encapsulating non‐interlocked discrete Pd
6 molecular prism [{Pd(en)}
6(bpy)
3(tma)
2(H
3tma)
2][NO
3]
6 ( 2 ). Though the same reaction using
cis‐[Pd(NO
3)
2(pn)] (pn=propane‐1,2‐diamine) instead of
cis‐[Pd(en)(NO
3)
2] gave triply interlocked coordination cage [{Pd(pn)}
6(bpy)
3(tma)
2]
2[NO
3]
12 ( 3 ) along with non‐interlocked Pd
6 analogue [{Pd(pn)}
6(bpy)
3(tma)
2](NO
3)
6 ( 3′ ), and the presence of H
3tma as a guest gave H
3tma‐encapsulating molecular prism [{Pd(pn)}
6(bpy)
3(tma)
2(H
3tma)
2][NO
3]
6 ( 4 ) exclusively. In solution, the amount of 3′ decreases as the temperature is decreased, and in the solid state 3 is the sole product. Notably, an analogous reaction using the relatively short pillar pz (pz=pyrazine) instead of 4,4′‐bpy gave triply interlocked coordination cage [{Pd(pn)}
6(pz)
3(tma)
2]
2[NO
3]
12 ( 5 ) as the single product. Interestingly, the same reaction using slightly more bulky
cis‐[Pd(NO
3)
2(tmen)] (tmen=
N,
N,
N′,
N′‐tetramethylethylene diamine) instead of
cis‐[Pd(NO
3)
2(pn)] gave non‐interlocked [{Pd(tmen)}
6(pz)
3(tma)
2][NO
3]
6 ( 6 ) exclusively. Complexes 1 , 3 , and 5 represent the first examples of template‐free triply interlocked molecular prisms obtained through multicomponent self‐assembly. Formation of the complexes was supported by IR and multinuclear NMR (
1H and
13C) spectroscopy. Formation of guest‐encapsulating complexes ( 2 and 4 ) was confirmed by 2D DOSY and ROESY NMR spectroscopic analyses, whereas for complexes 1 , 3 , 5 , and 6 single‐crystal X‐ray diffraction techniques unambiguously confirmed their formation. The gross geometries of H
3tma‐encapsulating complexes 2 and 4 were obtained by universal force field (UFF) simulations.
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