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Switching the Conformation of 3,2':6',3″-tpy Domains in 4'-(4-n-Alkyloxyphenyl)-3,2':6',3″-Terpyridines.

ABSTRACT: The preparation and characterization of 4'-(4-n-octyloxyphenyl)-3,2':6',3″-terpyridine (8) and 4'-(4-n-nonyloxyphenyl)-3,2':6',3″-terpyridine (9) are reported. The single crystal structures of 4'-(4-n-hexyloxyphenyl)-3,2':6',3″-terpyridine (6), 4'-(4-n-heptyloxyphenyl)-3,2':6',3″-terpyridine (7), and compounds 8 and 9 have been determined. The conformation of the 3,2':6',3″-tpy unit is trans,trans in 6 and 7, but switches to cis,trans in 8 and 9. This is associated with significant changes in the packing interactions with a more dominant role for van der Waals interactions between adjacent n-alkyloxy chains and C-Hmethylene... π interactions in 8 and 9. The solid-state structures of 6 and 7 with the n-hexyloxy and n-heptyloxy chains feature interwoven sheets of supramolecular assemblies of molecules, with pairs of n-alkyloxy chains threaded through cavities in an adjacent sheet.

SUBMITTER: Rocco D

PROVIDER: S-EPMC7397000 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Switching the Conformation of 3,2':6',3″-tpy Domains in 4'-(4-n-Alkyloxyphenyl)-3,2':6',3″-Terpyridines.

Rocco Dalila D Prescimone Alessandro A Constable Edwin C EC Housecroft Catherine E CE

Molecules (Basel, Switzerland) 20200710 14

The preparation and characterization of 4'-(4-n-octyloxyphenyl)-3,2':6',3″-terpyridine (8) and 4'-(4-n-nonyloxyphenyl)-3,2':6',3″-terpyridine (9) are reported. The single crystal structures of 4'-(4-n-hexyloxyphenyl)-3,2':6',3″-terpyridine (6), 4'-(4-n-heptyloxyphenyl)-3,2':6',3″-terpyridine (7), and compounds 8 and 9 have been determined. The conformation of the 3,2':6',3″-tpy unit is trans,trans in 6 and ...[more]

PMID: 32664337

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