1 Citation (Scopus)

Abstract

This work represents the first systematic study comparing a homologous series of alkali-based ionic liquids (ILs) - potassium 1-alkyl-3-methylcyclopentadienyl, K[C n C 1 Cp] - with their charge-inverted counterparts of the 1-alkyl-3-methylimidazolium chloride series, [C n C 1 Im]Cl. Three new compounds of the K[C n C 1 Cp] (n = 2, 8, or 10) were synthesized, purified, and analyzed by nuclear magnetic resonance, completing the series of previously reported derivatives (n = 4, 6). Further characterization involved differential scanning calorimetry and powder X-ray diffraction determinations. The results show that most of the alkali-based salts exhibit melting temperature values in the range commonly observed for halide-based ILs. However, striking structural differences were revealed by both X-ray diffraction and molecular dynamics results. These findings are consistent with the fact that alkali metal cations are efficient electron acceptors that can participate in interactions with a significant covalent character, namely, with aromatic moieties present in the cyclopentadienyl anions. This new concept extends the boundaries of ILs from the realm of noncovalent electrostatic systems to that of coordination chemistry.

Original languageEnglish
Pages (from-to)5804-5811
JournalJournal of Physical Chemistry C
Volume123
Issue number9
DOIs
Publication statusPublished - 8 Feb 2019

Fingerprint

Ionic Liquids
Ionic liquids
Electrostatics
alkalies
liquid potassium
Alkalies
chemistry
electrostatics
liquids
diffraction
alkali metals
Alkali Metals
halides
x rays
heat measurement
chlorides
melting
Alkali metals
molecular dynamics
anions

Cite this

@article{2fa63d06ef244dc3a0c3431eb3fc9fba,
title = "Ionic Liquids in Wonderland: from Electrostatics to Coordination Chemistry",
abstract = "This work represents the first systematic study comparing a homologous series of alkali-based ionic liquids (ILs) - potassium 1-alkyl-3-methylcyclopentadienyl, K[C n C 1 Cp] - with their charge-inverted counterparts of the 1-alkyl-3-methylimidazolium chloride series, [C n C 1 Im]Cl. Three new compounds of the K[C n C 1 Cp] (n = 2, 8, or 10) were synthesized, purified, and analyzed by nuclear magnetic resonance, completing the series of previously reported derivatives (n = 4, 6). Further characterization involved differential scanning calorimetry and powder X-ray diffraction determinations. The results show that most of the alkali-based salts exhibit melting temperature values in the range commonly observed for halide-based ILs. However, striking structural differences were revealed by both X-ray diffraction and molecular dynamics results. These findings are consistent with the fact that alkali metal cations are efficient electron acceptors that can participate in interactions with a significant covalent character, namely, with aromatic moieties present in the cyclopentadienyl anions. This new concept extends the boundaries of ILs from the realm of noncovalent electrostatic systems to that of coordination chemistry.",
author = "Cruz, {Tiago F. C.} and Karina Shimizu and Esperan{\cc}a, {Jos{\'e} M. S. S.} and V{\^a}nia Andr{\'e} and Duarte, {M. Teresa} and Rebelo, {Lu{\'i}s P. N.} and Gomes, {Pedro T.} and Lopes, {Jos{\'e} N. Canongia}",
year = "2019",
month = "2",
day = "8",
doi = "10.1021/acs.jpcc.9b00987",
language = "English",
volume = "123",
pages = "5804--5811",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "AMER CHEMICAL SOC",
number = "9",

}

Ionic Liquids in Wonderland: from Electrostatics to Coordination Chemistry. / Cruz, Tiago F. C.; Shimizu, Karina; Esperança, José M. S. S.; André, Vânia; Duarte, M. Teresa; Rebelo, Luís P. N.; Gomes, Pedro T.; Lopes, José N. Canongia.

In: Journal of Physical Chemistry C, Vol. 123, No. 9, 08.02.2019, p. 5804-5811.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Ionic Liquids in Wonderland: from Electrostatics to Coordination Chemistry

AU - Cruz, Tiago F. C.

AU - Shimizu, Karina

AU - Esperança, José M. S. S.

AU - André, Vânia

AU - Duarte, M. Teresa

AU - Rebelo, Luís P. N.

AU - Gomes, Pedro T.

AU - Lopes, José N. Canongia

PY - 2019/2/8

Y1 - 2019/2/8

N2 - This work represents the first systematic study comparing a homologous series of alkali-based ionic liquids (ILs) - potassium 1-alkyl-3-methylcyclopentadienyl, K[C n C 1 Cp] - with their charge-inverted counterparts of the 1-alkyl-3-methylimidazolium chloride series, [C n C 1 Im]Cl. Three new compounds of the K[C n C 1 Cp] (n = 2, 8, or 10) were synthesized, purified, and analyzed by nuclear magnetic resonance, completing the series of previously reported derivatives (n = 4, 6). Further characterization involved differential scanning calorimetry and powder X-ray diffraction determinations. The results show that most of the alkali-based salts exhibit melting temperature values in the range commonly observed for halide-based ILs. However, striking structural differences were revealed by both X-ray diffraction and molecular dynamics results. These findings are consistent with the fact that alkali metal cations are efficient electron acceptors that can participate in interactions with a significant covalent character, namely, with aromatic moieties present in the cyclopentadienyl anions. This new concept extends the boundaries of ILs from the realm of noncovalent electrostatic systems to that of coordination chemistry.

AB - This work represents the first systematic study comparing a homologous series of alkali-based ionic liquids (ILs) - potassium 1-alkyl-3-methylcyclopentadienyl, K[C n C 1 Cp] - with their charge-inverted counterparts of the 1-alkyl-3-methylimidazolium chloride series, [C n C 1 Im]Cl. Three new compounds of the K[C n C 1 Cp] (n = 2, 8, or 10) were synthesized, purified, and analyzed by nuclear magnetic resonance, completing the series of previously reported derivatives (n = 4, 6). Further characterization involved differential scanning calorimetry and powder X-ray diffraction determinations. The results show that most of the alkali-based salts exhibit melting temperature values in the range commonly observed for halide-based ILs. However, striking structural differences were revealed by both X-ray diffraction and molecular dynamics results. These findings are consistent with the fact that alkali metal cations are efficient electron acceptors that can participate in interactions with a significant covalent character, namely, with aromatic moieties present in the cyclopentadienyl anions. This new concept extends the boundaries of ILs from the realm of noncovalent electrostatic systems to that of coordination chemistry.

UR - http://www.scopus.com/inward/record.url?scp=85062356869&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.9b00987

DO - 10.1021/acs.jpcc.9b00987

M3 - Article

VL - 123

SP - 5804

EP - 5811

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 9

ER -