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Use of a cyclo-P₄ building block - a way to networks of host-guest assemblies.

ABSTRACT: Despite the proven ability to form supramolecular assemblies via coordination to copper halides, organometallic building blocks based on four-membered cyclo-P₄ ligands find only very rare application in supramolecular chemistry. To date, only three types of supramolecular aggregates were obtained based on the polyphosphorus end-deck complexes Cp^RTa(CO)₂(η⁴-P₄) (1a: Cp^R = Cp''; 1b: Cp^R = Cp'''), with none of them, however, possessing a guest-accessible void. To achieve this target, the use of silver salts of the weakly coordinating anion SbF₆ ^- was investigated as to their self-assembly in the absence and in the presence of the template molecule P₃Se₄. The two-component self-assembly of the building block 1a and the coinage-metal salt AgSbF₆ leads to the formation of 1D or 3D coordination polymers. However, when the template-driven self-assembly was attempted in the presence of an aliphatic dinitrile, the unprecedented barrel-like supramolecular host-guest assembly P₃Se₄@[{(Cp''Ta(CO)₂(η⁴-P₄))Ag}₈]⁸⁺ of 2.49 nm in size was formed. Moreover, cyclo-P₄-based supramolecules are connected in a 2D coordination network by dinitrile linkers. The obtained compounds were characterised by mass-spectrometry, ¹H and ³¹P NMR spectroscopy and X-ray structure analysis.

SUBMITTER: Peresypkina E

PROVIDER: S-EPMC8163406 | biostudies-literature |

REPOSITORIES: biostudies-literature

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