Phosphazenyl Phosphine Proton Sponges: Does the Proton-Chelating Effect Enhance Their Basicity?
Abstract
1. Introduction
2. Results and Discussion
2.1. Hydrogen Bond in Phosphine Dimers
2.2. Proton-Chelating Effect in Bisphosphazenyl Phosphines
2.3. Basicity in Acetonitrile
2.4. AIM and NBO Analysis
3. Computational Details
ΔGsol(A) − ΔGsol(BH+) + ΔGsol(AH+)}/2.303RT
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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PH3 | P(CH3)3 | P(Ph)3 | P(tmg)3 | P(imme)3 | (dmaP)3P | (pyrrP)3P | N(CH3)3 | |
---|---|---|---|---|---|---|---|---|
HF | 4.4 | 9.1 | 9.0 | 15.2 (18.3) | 17.9 (23.8) | 18.4 (18.8) | pta (23.8) | 14.9 |
PH4+ | PH(CH3)3+ | PH(Ph)3+ | PH(tmg)3+ | PH(imme)3+ | (dma)P3PH+ | (pyrr)P3PH+ | NH(CH3)3+ | |
NH3 | pt b | 10.3 | 8.3 | 3.6 | 6.0 | 3.3 | 4.9 | 20.1 |
Molecule | PA | GB | Molecule | PA | GB | ΔPA | En | Ep |
---|---|---|---|---|---|---|---|---|
1aa | 292.9 | 285.1 | 1a | 281.5 | 273.5 | 11.4 | 3.6 | −7.8 |
1bb | 301.0 | 292.4 | 1b | 284.5 | 276.7 | 16.5 | 2.9 | −13.7 |
2aa | 292.7 | 284.8 | 2a | 280.9 | 274.5 | 11.8 | 2.1 | −9.7 |
2bb | 297.7 | 290.8 | 2b | 288.1 | 279.3 | 9.6 | −1.5 | −11.1 |
3aa | 291.2 | 283.9 | 3a | 278.7 | 272.3 | 12.6 | 3.2 | −9.4 |
3bb | 296.8 | 291.1 | 3b | 283.8 | 276.5 | 13.0 | −1.2 | −14.2 |
4aa | 291.1 | 283.7 | 4a | 280.1 | 272.5 | 10.9 | 1.3 | −9.6 |
4bb | 295.8 | 289.0 | 4b | 284.3 | 276.9 | 11.5 | −3.9 | −15.4 |
5aa | 294.0 | 286.4 | 5a | 280.8 | 273.9 | 13.2 | −2.0 | −15.2 |
5bb | 295.5 | 288.4 | 5b | 286.7 | 278.6 | 8.8 | −9.0 | −17.9 |
6aa | 292.0 | 285.4 | 6a | 283.0 | 275.6 | 9.1 | 0.7 | −8.4 |
6bb | 299.1 | 292.8 | 6b | 288.6 | 280.8 | 10.5 | 0.5 | −10.1 |
7aa | 290.7 | 283.4 | 7a | 279.9 | 273.6 | 10.8 | −2.9 | −13.7 |
7bb | 296.8 | 289.4 | 7b | 285.7 | 277.9 | 11.1 | 0.5 | −10.6 |
8aa | 296.8 | 288.6 | 8a | 282.6 | 276.0 | 14.2 | −4.0 | −18.2 |
8bb | 307.0 | 296.3 | 8b | 288.8 | 282.2 | 18.1 | 1.1 | −17.0 |
9aa | 292.8 | 285.4 | 9a | 282.1 | 275.6 | 10.7 | 0.0 | −10.7 |
9bb | 300.6 | 294.2 | 9b | 289.7 | 281.3 | 10.8 | −5.7 | −16.6 |
10aa | 296.6 | 288.4 | 10a | 282.0 | 275.6 | 14.6 | 5.7 | −8.9 |
10bb | 305.3 | 297.8 | 10b | 288.8 | 282.1 | 16.5 | −2.7 | −19.3 |
(dmaP)3P | 297.4 | 291.3 | (pyrrP)3P | 307.5 | 300.2 |
Molecule | PA | GB | Molecule | PA | GB | ΔPA | En | Ep |
---|---|---|---|---|---|---|---|---|
Iaa | 286.2 | 277.5 | Ia | 281.5 | 274.1 | 4.7 | −0.2 | −4.9 |
Ibb | 293.1 | 285.4 | Ib | 287.3 | 279.5 | 5.9 | −3.0 | −8.9 |
IIaa | 288.6 | 281.5 | IIa | 282.4 | 275.0 | 6.1 | −0.3 | −6.4 |
IIbb | 293.5 | 285.4 | IIb | 289.2 | 282.2 | 4.3 | −9.4 | −13.7 |
IIIaa | 284.1 | 275.3 | IIIa | 281.1 | 273.2 | 3.0 | −3.3 | −6.3 |
IIIbb | 289.7 | 281.6 | IIIb | 287.9 | 281.2 | 1.8 | −10.0 | −11.8 |
IVaa | 287.2 | 280.2 | Iva | 281.2 | 273.2 | 6.0 | 0.6 | −5.4 |
IVbb | 294.7 | 284.5 | IVb | 288.4 | 281.8 | 6.4 | −8.9 | −15.3 |
Vaa | 285.3 | 277.5 | Vbb | 280.5 | 273.3 | 4.8 | 0.2 | −4.6 |
Vbb | 290.6 | 285.1 | Vb | 287.6 | 279.9 | 3.0 | −1.6 | −4.5 |
VIaa | 287.5 | 279.8 | Via | 282.8 | 275.9 | 4.7 | −0.3 | −5.0 |
VIbb | 291.3 | 283.7 | VIb | 286.9 | 280.3 | 4.4 | −1.7 | −6.1 |
VIIaa | 286.3 | 279.6 | VIIa | 281.1 | 273.9 | 5.3 | 0.1 | −5.2 |
VIIbb | 292.8 | 284.7 | VIIb | 287.0 | 279.9 | 5.8 | −1.9 | −7.7 |
VIIIaa | 288.6 | 279.6 | VIIIa | 282.7 | 276.3 | 5.9 | −3.9 | −9.8 |
VIIIbb | 293.2 | 286.2 | VIIIb | 289.3 | 281.1 | 4.1 | −8.8 | −11.7 |
IXaa | 287.7 | 280.5 | IXa | 282.0 | 274.7 | 5.6 | −2.0 | −7.6 |
IXbb | 289.5 | 282.3 | IXb | 288.0 | 280.2 | 1.6 | −5.7 | −7.3 |
Molecule | M1 | M2 | Molecule | M1 | M2 | ||||
---|---|---|---|---|---|---|---|---|---|
pKa1 | pKa2 | pKa1 | pKa2 | pKa1 | pKa2 | pKa1 | pKa2 | ||
1aa | 34.0 | 29.9 | 36.2 | 29.7 | 6aa | 35.0 | 29.4 | 38.2 | 27.4 |
1bb | 36.0 | 30.0 | 36.5 | 28.4 | 6bb | 37.0 | 30.7 | 37.2 | 29.4 |
2aa | 34.2 | 28.5 | 36.2 | 27.9 | 7aa | 33.4 | 28.7 | 33.2 | 31.2 |
2bb | 38.9 | 33.1 | 37.5 | 31.0 | 7bb | 34.9 | 30.2 | 35.9 | 28.9 |
3aa | 34.1 | 26.2 | 35.2 | 25.6 | 8aa | 36.3 | 33.5 | 36.4 | 31.8 |
3bb | 39.5 | 30.7 | 33.7 | 32.1 | 8bb | 37.5 | 35.8 | 38.5 | 29.8 |
4aa | 33.5 | 28.3 | 34.7 | 27.8 | 9aa | 35.3 | 31.2 | 37.0 | 29.2 |
4bb | 37.2 | 31.4 | 36.4 | 31.6 | 9bb | 40.2 | 36.6 | 39.6 | 34.8 |
5aa | 30.5 | 31.3 | 34.0 | 28.3 | 10aa | 37.8 | 30.3 | 36.9 | 29.4 |
5bb | 32.8 | 32.8 | 31.9 | 33.5 | 10bb | 42.0 | 34.6 | 39.2 | 35.2 |
Compound | BCP | ρ(rc) a | V(rc) b | E c |
---|---|---|---|---|
1aa, H+ | P···H–+P | 0.0220 | −0.0147 | −2.96 |
1bb, H+ | P···H–+P | 0.0225 | −0.0151 | −3.02 |
2aa, H+ | P···H–+P | 0.0262 | −0.0171 | −3.40 |
2bb, H+ | P···H–+P | 0.0226 | −0.0164 | −3.27 |
Nimine···H–+P | 0.0236 | −0.0175 | −3.46 | |
3aa, H+ | P···H–+P | 0.0293 | −0.0195 | −3.84 |
3bb, H+ | P···H–+P | 0.0229 | −0.0167 | −3.34 |
4aa, H+ | P···H–+P | 0.0208 | −0.0132 | −2.71 |
4bb, H+ | P···H–+P | 0.0350 | −0.0238 | −4.53 |
5aa, H+ | Nimine···H–+P | 0.0147 | −0.0093 | −2.02 |
5bb, H+ | Nimine···H–+P | 0.0185 | −0.0124 | −2.58 |
6aa, H+ | P···H–+P | 0.0173 | −0.0093 | −2.02 |
6bb, H+ | P···H–+P | 0.0220 | −0.0136 | −2.77 |
7aa, H+ | P···H–+P | 0.0170 | −0.0091 | −2.02 |
7bb, H+ | P···H–+P | 0.0213 | −0.0131 | −2.71 |
8aa, H+ | P···H–+P | 0.0191 | −0.0113 | −2.40 |
8bb, H+ | P···H–+P | 0.0171 | −0.0104 | −2.21 |
9aa, H+ | P···H–+P | 0.0197 | −0.0116 | −2.46 |
9bb, H+ | P···H–+P | 0.0188 | −0.0111 | −2.33 |
10aa, H+ | P···H–+P | 0.0205 | −0.0124 | −2.58 |
10bb, H+ | P···H–+P | 0.0210 | −0.0135 | −2.77 |
TPPN, H+ | N···H–+N | 0.0545 | −0.0460 | −8.42 |
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Glasovac, Z.; Barić, D.; Despotović, I.; Kovačević, B. Phosphazenyl Phosphine Proton Sponges: Does the Proton-Chelating Effect Enhance Their Basicity? Int. J. Mol. Sci. 2025, 26, 5058. https://doi.org/10.3390/ijms26115058
Glasovac Z, Barić D, Despotović I, Kovačević B. Phosphazenyl Phosphine Proton Sponges: Does the Proton-Chelating Effect Enhance Their Basicity? International Journal of Molecular Sciences. 2025; 26(11):5058. https://doi.org/10.3390/ijms26115058
Chicago/Turabian StyleGlasovac, Zoran, Danijela Barić, Ines Despotović, and Borislav Kovačević. 2025. "Phosphazenyl Phosphine Proton Sponges: Does the Proton-Chelating Effect Enhance Their Basicity?" International Journal of Molecular Sciences 26, no. 11: 5058. https://doi.org/10.3390/ijms26115058
APA StyleGlasovac, Z., Barić, D., Despotović, I., & Kovačević, B. (2025). Phosphazenyl Phosphine Proton Sponges: Does the Proton-Chelating Effect Enhance Their Basicity? International Journal of Molecular Sciences, 26(11), 5058. https://doi.org/10.3390/ijms26115058