Related Experiment Video
Updated: Mar 13, 2026

Analysis of Volatile and Oxidation Sensitive Compounds Using a Cold Inlet System and Electron Impact Mass Spectrometry
Published on: September 5, 2014
Tris(imidazolin-2-ylidenamino)phosphine: A Crystalline Phosphorus(III) Superbase That Splits Carbon Dioxide
Paul Mehlmann1, Christian Mück-Lichtenfeld2, Tristan T Y Tan1
1Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 30, 48149, Münster, Germany.
Abstract:
We report the synthesis and remarkable properties of the phosphine P(NIiPr)3 (NIiPr=1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidenamino), a crystalline solid accessible through a short and scalable route. Evaluation of the electron-donor properties reveals a Tolman electronic parameter (TEP) value of 2029.7 cm-1 for the new phosphine that is significantly lower than those of all known phosphines or even N-heterocyclic carbenes. Moreover, P(NIiPr)3 is more basic [pKBH+ (MeCN)=38.8] than Verkade's proazaphosphatranes, thus being the strongest reported nonionic phosphorus(III) superbase. The coordination chemistry of the new phosphine towards different metal centers has been explored, and due to its unique electron-releasing character, the phosphine is capable of capturing and cleaving the CO2 molecule.
Related Concept Videos
Aldehydes and Ketones to Alkenes: Wittig Reaction Mechanism
The reaction begins with the nucleophilic addition between a phosphorus ylide and the carbonyl compound. Due to its carbanionic character, phosphorus ylide acts as a strong nucleophile and attacks the electrophilic carbonyl group. This generates a charge-separated dipolar intermediate called betaine. The negatively charged oxygen atom and...
Predicting Molecular Geometry
Hybridization of Atomic Orbitals II
Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...
Aldehydes and Ketones to Alkenes: Wittig Reaction Overview
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...

