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Homochiral Self-Sorted and Emissive IrIII Metallo-Cryptophanes.

ABSTRACT: The racemic ligands (±)-tris(isonicotinoyl)-cyclotriguaiacylene (L1), or (±)-tris(4-pyridyl-methyl)-cyclotriguaiacylene (L2) assemble with racemic (?,?)-[Ir(ppy)2 (MeCN)2 ]+ , in which ppy=2-phenylpyridinato, to form [{Ir(ppy)2 }3 (L)2 ]3+ metallo-cryptophane cages. The crystal structure of [{Ir(ppy)2 }3 (L1)2 ]?3BF4 has MM-??? and PP-??? isomers, and homochiral self-sorting occurs in solution, a process accelerated by a chiral guest. Self-recognition between L1 and L2 within cages does not occur, and cages show very slow ligand exchange. Both cages are phosphorescent, with [{Ir(ppy)2 }3 (L2)2 ]3+ having enhanced and blue-shifted emission when compared with [{Ir(ppy)2 }3 (L1)2 ]3+ .

SUBMITTER: Pritchard VE

PROVIDER: S-EPMC5499720 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Homochiral Self-Sorted and Emissive IrIII Metallo-Cryptophanes.

Pritchard Victoria E VE Rota Martir Diego D Oldknow Samuel S Kai Shumpei S Hiraoka Shuichi S Cookson Nikki J NJ Zysman-Colman Eli E Hardie Michaele J MJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20170420 26

The racemic ligands (±)-tris(isonicotinoyl)-cyclotriguaiacylene (L1), or (±)-tris(4-pyridyl-methyl)-cyclotriguaiacylene (L2) assemble with racemic (Λ,Δ)-[Ir(ppy)2 (MeCN)2 ]+ , in which ppy=2-phenylpyridinato, to form [{Ir(ppy)2 }3 (L)2 ]3+ metallo-cryptophane cages. The crystal structure of [{Ir(ppy)2 }3 (L1)2 ]⋅3BF4 has MM-ΛΛΛ and PP-ΔΔΔ isomers, and homochiral self-sorting o ...[more]

PMID: 28370620

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