Ligand and counterion control of Ag(I) architectures: Assembly of a {Ag-8} ring cluster mediated by hydrophobic and Ag center dot center dot center dot Ag interactions

TitleLigand and counterion control of Ag(I) architectures: Assembly of a {Ag-8} ring cluster mediated by hydrophobic and Ag center dot center dot center dot Ag interactions
Publication TypeJournal Article
Year of Publication2007
AuthorsFielden J, Long DL, Slawin AMZ, Kogerler P, Cronin L
Journal TitleInorganic Chemistry
Volume46
Pages9090-9097
Date PublishedOct
Type of ArticleArticle
ISBN Number0020-1669
Accession NumberISI:000250345400018
KeywordsALIPHATIC AMINO LIGANDS, chemistry, COORDINATION POLYMERS, COPPER(II), DINUCLEAR, nanoparticles, networks, RESONANCE-SPECTROSCOPY, SILVER(I) COMPLEXES, TETRANUCLEAR
Abstract

A strategy combining ligand design and counterion variation has been used to investigate the assembly of silver(I) complexes. As a result, dinuclear, octanuclear, and polymeric silver(I) species have been synthesized by complexation of the rigid aliphatic amino ligands cis-3,5-diamino-trans-hydroxycyclohexane (DAHC), cis-3,5-diamino- transmethoxycyclohexane (DAMC), and cis-3,5-diamino-trans-tert-butyidimethylsilylanyloxycyclohexane (DATC) with silver(I) triflate, nitrate, and perchlorate. The compositions of these aggregates, established by X-ray crystallography and elemental analysis, are [fAg(DAHC)}(2)](CF3SO3)(2) (1), [{Ag(DAMC)}(2)](CF3SO3)(2) (2), [{Ag(DAMC)}(2)](NO3)(2) (3), [{Ag-(DATC)}(6){Ag(DAHC)}(2)](NO3)(8) (4), and [{Ag(DATC}(n)](NO3)(n) (5), where the DAHC present in 4 is formed by in situ hydrolysis of the acid labile silyl ether group. The type of aggregate formed depends both upon the noncoordinating O-substituent of the ligand and the (also noncoordinating) counterion, with the normal preference of the ligand topology for forming Ag2L2 structures being broken by introduction of the bulky, lipophilic O-tert-butyidimethylsilyl (TBDMS) group. Of particular note is the octanuclear silver ring structure 4, which is isolated only when both the O-TBDMS group and the nitrate counteranion are present and is formed from four Ag2L2 dimers; connected by Ag center dot center dot center dot Ag and hydrogen-bonding interactions. Diffusion rate measurement of this {Ag-8} complex by H-1 NMR (DOSY) indicates dissociation in CD3OD and CD3CN, showing that this supramolecular ring structure is formed upon crystallization, and establishing a qualitative limit to the strength of Ag center dot center dot center dot Ag interactions in solution. When solutions of the {Ag-8} cluster in methanol are kept for several days though, a new UV-vis absorption is observed at around 430 nm, consistent with the formation of silver nanoparticles.

DOI10.1021/ic700872b
Alternate JournalInorg. Chem.