Predicted Gas-Phase and Liquid-Phase Acidities of Carborane Carboxylic and Dicarboxylic Acids

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388980%3A_____%2F18%3A00489465" target="_blank" >RIV/61388980:_____/18:00489465 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1002/slct.201800683" target="_blank" >http://dx.doi.org/10.1002/slct.201800683</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/slct.201800683" target="_blank" >10.1002/slct.201800683</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Predicted Gas-Phase and Liquid-Phase Acidities of Carborane Carboxylic and Dicarboxylic Acids

Popis výsledku v původním jazyce

By means of MP2 and DFT computations we predict gas-phase acidities and liquid-phase (MeCN) acidities of (di)carboxylic acids derived from icosahedral ortho, meta, and para-carboranes. For comparative purpose, we include the benzoic and phthalic acids. Substitution of benzene by a carborane cage – cage effect – strikingly increases the gas-phase acidity (lower GA) for the (di)carboxylic acids, being the ortho isomers always the most acidic, following the order ortho ≫ meta > para. The computed GA of the dicarboxylic acid derived from ortho-carborane is far lower than sulphuric acid, due to an enhanced stabilization of the carboxylate through an intramolecular OHO bridge connection, also taking place in phthalic acid. The change of GA relative to ortho, meta and para positions of the carboxylic groups isomer effect is larger for carboranes. As regards to liquid-phase (MeCN), the computations show that carborane (di)carboxylic acids also show a larger acidity (lower pK a ) as compared to the phthalic acids and that the dicarboxylic ortho-carborane is also a superacid in the liquid phase (MeCN), due to the OHO bridge connection in the carboxylate, as in the gas phase. Additional computations show how much of this isomeric effect is to be attributed to the electronic delocalization.

Název v anglickém jazyce

Predicted Gas-Phase and Liquid-Phase Acidities of Carborane Carboxylic and Dicarboxylic Acids

Popis výsledku anglicky

By means of MP2 and DFT computations we predict gas-phase acidities and liquid-phase (MeCN) acidities of (di)carboxylic acids derived from icosahedral ortho, meta, and para-carboranes. For comparative purpose, we include the benzoic and phthalic acids. Substitution of benzene by a carborane cage – cage effect – strikingly increases the gas-phase acidity (lower GA) for the (di)carboxylic acids, being the ortho isomers always the most acidic, following the order ortho ≫ meta > para. The computed GA of the dicarboxylic acid derived from ortho-carborane is far lower than sulphuric acid, due to an enhanced stabilization of the carboxylate through an intramolecular OHO bridge connection, also taking place in phthalic acid. The change of GA relative to ortho, meta and para positions of the carboxylic groups isomer effect is larger for carboranes. As regards to liquid-phase (MeCN), the computations show that carborane (di)carboxylic acids also show a larger acidity (lower pK a ) as compared to the phthalic acids and that the dicarboxylic ortho-carborane is also a superacid in the liquid phase (MeCN), due to the OHO bridge connection in the carboxylate, as in the gas phase. Additional computations show how much of this isomeric effect is to be attributed to the electronic delocalization.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10402 - Inorganic and nuclear chemistry

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2018

Kód důvěrnosti údajů

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

Název periodika

ChemistrySelect

ISSN

2365-6549

e-ISSN

—

Svazek periodika

3

Číslo periodika v rámci svazku

16

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

10

Strana od-do

4344-4353

Kód UT WoS článku

000431626800031

EID výsledku v databázi Scopus

2-s2.0-85046079652