Diferrocenes Bridged by a Geminal Diethynylethene Scaffold with Varying Pendant Substituents: Electronic Interactions in Cross-Conjugated System

A series of geminal diethynylethene (gem-DEE) bridged diferrocenyl compounds with varying pendant substituents at the side chain, including xanthene, thioxanthene, dibenzo[a,d]cycloheptene, and fluorene, is reported with the aim of exploring electronic interactions in the cross-conjugated system. Th...

Full description

Saved in:
Bibliographic Details
Published in:Organometallics Vol. 36; no. 21; pp. 4278 - 4286
Main Authors: Fan, Yang, Li, Hua-Min, Zou, Guo-Dong, Zhang, Xu, Pan, Ying-Le, Cao, Ke-Ke, Zhang, Meng-Li, Ma, Pei-Lin, Lu, Hai-Ting
Format: Journal Article
Language:English
Published: WASHINGTON Amer Chemical Soc 13.11.2017
Subjects:
Chemistry
Chemistry, Inorganic & Nuclear
Chemistry, Organic
Physical Sciences
Science & Technology
QUANTUM-INTERFERENCE
DIRUTHENIUM COMPLEXES
FERROCENE
DELTA-E-1/2 VALUES
RUTHENIUM COMPLEXES
DELOCALIZATION
MIXED-VALENCE CHEMISTRY
CHARGE-TRANSFER
SOLID-STATE
EXPANDED RADIALENES
ISSN:0276-7333, 1520-6041
Online Access:Get more information
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A series of geminal diethynylethene (gem-DEE) bridged diferrocenyl compounds with varying pendant substituents at the side chain, including xanthene, thioxanthene, dibenzo[a,d]cycloheptene, and fluorene, is reported with the aim of exploring electronic interactions in the cross-conjugated system. The compounds 9-[bis(ferrocenylethynyl)methylene]-9H-xanthene (1), 9-[bis(ferrocenylethynyl)methylene]-9H-thioxanthene (2), 5-[bis(ferrocenylethynyl)methylene]-5H-dibenzo[a,d]-cycloheptene (3), and 9-[bis(ferrocenylethynyl)methylene]-9H-fluorene (4) were synthesized and characterized by using spectroscopic methods and single-crystal X-ray diffraction analyses. Electrochemical measurements using the weakly coordinating electrolyte Na[B{C6H3(3,5-CF3)(2)}(4)] reveal the moderate electronic coupling between the ferrocenyl (Fc) termini. Hush analysis of the intervalence charge-transfer (IVCT) bands for the monocation species is suggestive of the weakly coupled Robin-Day class II mixed-valence compounds. DFT and TDDFT calculations suggest that the low-energy transitions of these compounds mainly involve a metal to ligand charge transfer (MLCT) transition from the iron center of ferrocenyl termini to the pendant substituent.
ISSN:0276-7333
1520-6041
DOI:10.1021/acs.organomet.7b00686