Premium
The Interconnection of Two Positive Charges by Conjugation and Cross‐Conjugation in Bis‐Quinolinium Ethynyls
Author(s) -
Batsyts Sviatoslav,
Hübner Eike G.,
Namyslo Jan C.,
Schmidt Andreas
Publication year - 2019
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201900816
Subject(s) - conjugated system , chemistry , raman spectroscopy , resonance (particle physics) , computational chemistry , photochemistry , organic chemistry , polymer , atomic physics , physics , optics
1,4‐Diethynylbenzene was used as conjugated all‐carbon and rigid spacer between the 2‐, 3‐ and 4‐positions of two 1‐methylquinolinium rings. Thus, for a systematic study, a series of dicationic salts with 2,2‐, 3,3‐, 4,4‐, 3,2‐, and 3,4‐interconnections of the two positive charges was prepared, in which all even‐numbered substitution patterns are conjugated, and all odd‐numbered substitution patterns are cross‐conjugated. As a consequence, conjugated/conjugated, cross‐conjugated/cross‐conjugated, and conjugated/cross‐conjugated dications have been prepared. The different combinations result in considerably different charge distributions of the positive charges within the π‐electron systems according to the rules of resonance which translate into different DFT‐calculated frontier orbital profiles and spectroscopic properties such as 13 C NMR chemical shifts, IR and Raman absorptions, and the measured as well as calculated UV/Vis spectra.