Search results for "Cross-conjugation"

Molecule Isomerism Modulates the Diradical Properties of Stable Singlet Diradicaloids

2019

Inclusion of quinoidal cores in conjugated hydrocarbons is a common strategy to modulate the properties of diradicaloids formed by aromaticity recovery within the quinoidal unit. Here we describe an alternative approach of tuning of diradical properties in indenoindenodibenzothiophenes upon anti → syn isomerism of the benzothiophene motif. This alters the relationship of the S atom with the radical center from linear to cross conjugation yet retains the same 2,6-naphtho conjugation pattern of the rearomatized core. We conduct a full comparison between the anti and syn derivatives based on structural, spectroscopic, theoretical, and magnetic measurements, showing that these systems are stabl…

Synthese von Oligo(p-phenylen-m-pyridindiyl)en

2000

Gekreuzt konjugierte oligomere aus pyrrol-, benzol- und carbonyl-Bausteinen

2004

Abstract Chalcones can serve as C 2 or C 3 components for the formation of 1 H -pyrroles. In particular the reaction with tosylisocyanid could be applied to the oligochalcones 2d - g with up to 6 enone units. A series of cross-conjugated oligomers 8d - g was obtained; these compounds consist of a chain of 1,4-phenylene, carbonyl and 1 H -pyrrole-3,4-diyl building blocks. The benzene rings bear two propoxy sidechains in order to enhance the solubility.

2-[4-(Di­methyl­amino)­phen­yl]-3,3-di­fluoro-3H-naphtho­[1,2-e][1,3,2]oxaza­borinin-2-ium-3-uide

2017

In the title compound, C19H17BF2N2O, a twist about the N—C single bond is observed, making the cross conjugation not as efficient as in the case of a planar structure. The borone complex has tetrahedral geometry. In the crystal, molecules are conected by weak C—H...F hydrogen bonds.