Bulk Inclusions of Double Pyridazine Molecular Rotors in Hexagonal Tris(o-phenylene)cyclotriphosphazene

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388963%3A_____%2F19%3A00507863" target="_blank" >RIV/61388963:_____/19:00507863 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11310/19:10396144

Výsledek na webu

<a href="https://pubs.acs.org/doi/10.1021/acs.joc.9b00553" target="_blank" >https://pubs.acs.org/doi/10.1021/acs.joc.9b00553</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.joc.9b00553" target="_blank" >10.1021/acs.joc.9b00553</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Bulk Inclusions of Double Pyridazine Molecular Rotors in Hexagonal Tris(o-phenylene)cyclotriphosphazene

Popis výsledku v původním jazyce

A new generation of double pyridazine molecular rotors differing in intramolecular dipole-dipole spacing was synthesized. All rotor molecules formed bulk inclusions in a tris(o-phenylenedioxy)cyclotriphosphazene (TPP) host. Results of dielectric spectroscopy were fitted to a pair of nine-state models that accounted for interactions of neighboring dipoles at either an aligned or opposed possible orientation of the local threefold dipole rotation potentials within a channel of the TPP host. The results indicate dipole- dipole interaction strengths at the 100 to 200 K scale that lead dipoles to preferentially populate a subset of low-energy configurations. They also reveal that pyridazines with ethynyl substituents in 3- and 6-positions have slightly higher rotational barriers (3.2-3.5 kcal/mol) than those carrying one ethynyl and one tert-butyl group (1.9-3.0 kcal/mol). Upon cooling, these barriers reduce the rate of thermal transitions between the potential wells so much that the inclusions cannot achieve ordered dipolar ground states.

Název v anglickém jazyce

Bulk Inclusions of Double Pyridazine Molecular Rotors in Hexagonal Tris(o-phenylene)cyclotriphosphazene

Popis výsledku anglicky

A new generation of double pyridazine molecular rotors differing in intramolecular dipole-dipole spacing was synthesized. All rotor molecules formed bulk inclusions in a tris(o-phenylenedioxy)cyclotriphosphazene (TPP) host. Results of dielectric spectroscopy were fitted to a pair of nine-state models that accounted for interactions of neighboring dipoles at either an aligned or opposed possible orientation of the local threefold dipole rotation potentials within a channel of the TPP host. The results indicate dipole- dipole interaction strengths at the 100 to 200 K scale that lead dipoles to preferentially populate a subset of low-energy configurations. They also reveal that pyridazines with ethynyl substituents in 3- and 6-positions have slightly higher rotational barriers (3.2-3.5 kcal/mol) than those carrying one ethynyl and one tert-butyl group (1.9-3.0 kcal/mol). Upon cooling, these barriers reduce the rate of thermal transitions between the potential wells so much that the inclusions cannot achieve ordered dipolar ground states.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10401 - Organic chemistry

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Organic Chemistry

ISSN

0022-3263

e-ISSN

—

Svazek periodika

84

Číslo periodika v rámci svazku

13

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

19

Strana od-do

8449-8467

Kód UT WoS článku

000474796800008

EID výsledku v databázi Scopus

2-s2.0-85067967686