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Ionic liquids of superior thermal stability. Validation of PPh₄ ⁺ as an organic cation of impressive thermodynamic durability.

ABSTRACT: Recent work by Wasserscheid, et al. suggests that PPh₄ ⁺ is an organic molecular ion of truly exceptional thermal stability. Herein we provide data that cements that conclusion: specifically, we show that aliphatic moieties of modified PPh₄ ⁺-based cations incorporating methyl, methylene, or methine C-H bonds burn away at high temperatures in the presence of oxygen, forming CO, CO₂, and water, leaving behind the parent ion PPh₄ ⁺. The latter then undergoes no further reaction, at least below 425 °C.

SUBMITTER: Soltani M

PROVIDER: S-EPMC9054240 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Ionic liquids of superior thermal stability. Validation of PPh4 + as an organic cation of impressive thermodynamic durability.

Soltani Mohammad M McGeehee Jimmie L JL Stenson Alexandra C AC O'Brien Richard A RA Duranty Edward R ER Salter E Alan EA Wierzbicki Andrzej A Glover T Grant TG Davis James H JH

RSC advances 20200529 35

Recent work by Wasserscheid, et al. suggests that PPh4 + is an organic molecular ion of truly exceptional thermal stability. Herein we provide data that cements that conclusion: specifically, we show that aliphatic moieties of modified PPh4 +-based cations incorporating methyl, methylene, or methine C-H bonds burn away at high temperatures in the presence of oxygen, forming CO, CO2, and water, leaving behind the parent ion PPh4</ ...[more]

PMID: 35517722

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