Predominant effect of connecting atom and position of substituents on azomethine nitrogens' basicity in phthalocyanines
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11160%2F16%3A10335427" target="_blank" >RIV/00216208:11160/16:10335427 - isvavai.cz</a>
Výsledek na webu
<a href="http://www.worldscientific.com/doi/full/10.1142/S1088424616500747" target="_blank" >http://www.worldscientific.com/doi/full/10.1142/S1088424616500747</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1142/S1088424616500747" target="_blank" >10.1142/S1088424616500747</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Predominant effect of connecting atom and position of substituents on azomethine nitrogens' basicity in phthalocyanines
Popis výsledku v původním jazyce
The basicity of azomethine nitrogens was studied on a series of phthalocyanines (Pcs) that differed in a position of substituent, i.e. peripherally (beta-series) and non-peripherally substituted Pcs (alpha-series), and in a type of substituent (alkylsulfanyl, alkyloxy or alkyl). Appropriate 3,6- or 4,5-disubstituted phthalonitriles were prepared either by nucleophilic substitution or by Negishi coupling. Target zinc Pcs were synthesized by Linstead method. The basicity was studied by the mean of absorption and H-1 NMR spectroscopies in chloroform upon titration with trifluoroacetic acid. Equilibrium constants (log K) indicated significant difference within the series. Basicity decreased as follows: alpha-alkyloxy >> alpha-alkylsulfanyl > beta-alkyloxy > beta-alkyl > beta-alkylsulfanyl similar to alpha-alkyl with log K higher than 7 down to 2.6 M-1. Increased basicity of alpha-alkyloxy and alpha-alkylsulfanyl Pcs is caused by the stabilization of trapped hydrogen at azomethine nitrogen via hydrogen bonding and van der Waals interactions, respectively. The basicity of beta-series clearly correlated with the electronic effects of substituents. H-1 NMR studies confirmed the possibility of the weak bonding interactions in alpha-alkyloxy and alpha-alkylsulfanyl Pcs, however, the position of the H-1 NMR signal of azomethine-NH proton was even more influenced by the electronic effects of present substituents than by the weak interactions.
Název v anglickém jazyce
Predominant effect of connecting atom and position of substituents on azomethine nitrogens' basicity in phthalocyanines
Popis výsledku anglicky
The basicity of azomethine nitrogens was studied on a series of phthalocyanines (Pcs) that differed in a position of substituent, i.e. peripherally (beta-series) and non-peripherally substituted Pcs (alpha-series), and in a type of substituent (alkylsulfanyl, alkyloxy or alkyl). Appropriate 3,6- or 4,5-disubstituted phthalonitriles were prepared either by nucleophilic substitution or by Negishi coupling. Target zinc Pcs were synthesized by Linstead method. The basicity was studied by the mean of absorption and H-1 NMR spectroscopies in chloroform upon titration with trifluoroacetic acid. Equilibrium constants (log K) indicated significant difference within the series. Basicity decreased as follows: alpha-alkyloxy >> alpha-alkylsulfanyl > beta-alkyloxy > beta-alkyl > beta-alkylsulfanyl similar to alpha-alkyl with log K higher than 7 down to 2.6 M-1. Increased basicity of alpha-alkyloxy and alpha-alkylsulfanyl Pcs is caused by the stabilization of trapped hydrogen at azomethine nitrogen via hydrogen bonding and van der Waals interactions, respectively. The basicity of beta-series clearly correlated with the electronic effects of substituents. H-1 NMR studies confirmed the possibility of the weak bonding interactions in alpha-alkyloxy and alpha-alkylsulfanyl Pcs, however, the position of the H-1 NMR signal of azomethine-NH proton was even more influenced by the electronic effects of present substituents than by the weak interactions.
Klasifikace
Druh
J<sub>x</sub> - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)
CEP obor
CC - Organická chemie
OECD FORD obor
—
Návaznosti výsledku
Projekt
<a href="/cs/project/GP14-02165P" target="_blank" >GP14-02165P: Červeně emitující fluorescenční senzory odvozené od struktury azaftalocyaninů: Studie aza-crownů jako rozpoznávací části</a><br>
Návaznosti
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Ostatní
Rok uplatnění
2016
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
Journal of Porphyrins and Phthalocyanines
ISSN
1088-4246
e-ISSN
—
Svazek periodika
20
Číslo periodika v rámci svazku
8-11
Stát vydavatele periodika
FR - Francouzská republika
Počet stran výsledku
12
Strana od-do
1122-1133
Kód UT WoS článku
000390248600027
EID výsledku v databázi Scopus
2-s2.0-84988613824