How To Insulate a Reactive Site from a Perfluoroalkyl Group:  Photoelectron Spectroscopy, Calorimetric, and Computational Studies of Long-Range Electronic Effects in Fluorous Phosphines P((CH2)m(CF2)7CF3)3

Jiao, Haijun; Stang, Sylvie Le; Soós, Tibor; Meier, Ralf; Kowski, Klaus; Rademacher, Paul; Jafarpour, Laleh; Hamard, Jean Benoit; Nolan, Steven P.; Gladysz, J. A.

doi:10.1021/ja011877g

Cited by 73 publications

(73 citation statements)

References 40 publications

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“…34,42 In other words, it directly corresponds to the difference between the potentials measured once with that electrode immersed in a solution of ion j and once immersed in a solution of ion i of the same concentration. Since it follows analogously that Φ j,co -Φ i,co equals , equation 4 can be reformed to (5) Therefore, the equilibrium constant describing the exchange of the two ions i and j between the two fluorous phases is given by: (6) Inclusion of the activity coefficients in the constant term gives the logarithm of the formal ion exchange constant, K, as:…”

Section: Resultsmentioning

confidence: 99%

Coordinative Properties of Highly Fluorinated Solvents with Amino and Ether Groups

et al. 2005

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In spite of the widespread use of perfluorinated solvents with amino and ether groups in a variety of application fields, the coordinative properties of these compounds are poorly known. It is generally assumed that the electron withdrawing perfluorinated moieties render these functional groups rather inert, but little is known quantitatively about the extent of their inertness. This paper reports on the interactions between inorganic monocations and perfluorotripentylamine and 2H-perfluoro-5,8,11-trimethyl-3,6,9,12-tetraoxapentadecane, as determined with fluorous liquid-membrane cationselective electrodes doped with tetrakis[3,5-bis(perfluorohexyl)phenyl]borate salts. The amine does not undergo measurable association with any ion tested, and its formal pK a is shown to be smaller than -0.5. This is consistent with the nearly planar structure of the amine at its nitrogen center, as obtained with density functional theory calculations. The tetraether interacts very weakly with Na + and Li + . Assuming 1:1 stoichiometry, formal association constants were determined to be 2.3 and 1.5 M -1 , respectively. This disproves an earlier proposition that the Lewis base character in such compounds may be non-existent. Due to the extremely low polarity of fluorous solvents and the resulting high extent of ion pair formation, a fluorophilic electrolyte salt with perfluoroalkyl substituents on both the cation and the anion had to be developed for these experiments. In its pure form, this first fluorophilic electrolyte salt is an ionic liquid with a glass transition temperature, T g , of -18.5 °C. Interestingly, the molar conductivity of solutions of this salt increases very steeply in the high concentration range, making it a particularly effective electrolyte salt.

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Section: Resultsmentioning

confidence: 99%

Coordinative Properties of Highly Fluorinated Solvents with Amino and Ether Groups

et al. 2005

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“…six methylene spacers are needed for "complete" insulation. 29 Thus, cyclic voltammograms were sought. However, when DMF and CH 3 CN solutions of 4-6 or 9 were treated with the supporting electrolyte (1), which has an extensively studied electrochemistry.…”

Section: Properties Of Fluorous Iron/sulfur Clustersmentioning

confidence: 99%

“…Regardless, this is a certainty from well established inductive effects. 29 Iron/sulfur clusters with fluorous thiolates will be electron deficient and therefore thermodynamically easier to reduce. This is reflected by less negative E 1/2 value of 4 (−2.32 V) versus 5 (−2.40 V), indicating a more facile reduction, consistent with the decreased methylene spacer length.…”

Section: Properties Of Fluorous Iron/sulfur Clustersmentioning

confidence: 99%

Phase and redox shifted four iron/four sulfur clusters: fluorous analogs of metalloenzyme cofactors

Zhang

Mueller

et al. 2015

Dalton Trans.

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Reactions of (1) 4 ], comprised of a fluorous dianion and in some cases fluorous cations, with (1) Q/n = Ph 4 P/2 (4, 67%), Ph 4 P/3 (5, 67%), Me 4 N/3 (69%), and Ph 3 P(CH 2 ) 2 R f6 /2 (73%) or (2) PhCH 2 P((CH 2 ) 3 R f6 ) 3 /2 (14, 39%), PhCH 2 P((CH 2 ) 3 R f6 ) 3 /3 (15, 63%), and PPN/2 (36% (FC-72/THF). Cyclic voltammograms carried out using a platinum working microelectrode show that 4 is 0.08 V thermodynamically easier to reduce than 5.

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“…[2a] and ref. [14] [g] The electronic effect of multiple substituents may be added up linearly, ref. [15] The value denoted here is 2 Â s m .…”

mentioning

confidence: 99%

Enhanced Hydrogenation Activity and Recycling of Cationic Rhodium Diphosphine Complexes through the Use of Highly Fluorous and Weakly‐Coordinating Tetraphenylborate Anions

Broeke

Wolf

Deelman³

et al. 2003

Adv Synth Catal

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The effect of the nature of the anion on the performance of ionic rhodium catalysts has received little attention. Herein it is shown that the use of highly fluorous tetraphenylborate anions can enhance catalyst activity in both conventional and fluorous media. À (1 g)} the activity towards the hydrogenation of 1-octene in acetone increased in the order 1c < 1b < 1e < 1a < 1d~1f < 1g with 1g being twice as active as the commonly applied 1a. Despite the fluorophilic character introduced by the substituted tetraarylborate anions, the presence of some perfluoroalkyl-substituents in the cation was still required for achieving high partition coefficients. À (2g)} were prepared, which were active in the hydrogenation of 1-octene, 2g even more so than 3f. Both these highly fluorous catalysts could be recycled with 99% efficiency through fluorous biphasic separation, whereas the corresponding BF 4 À complex of 2g (2a) did not show any affinity for the fluorous phase.

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How To Insulate a Reactive Site from a Perfluoroalkyl Group: Photoelectron Spectroscopy, Calorimetric, and Computational Studies of Long-Range Electronic Effects in Fluorous Phosphines P((CH₂)_m(CF₂)₇CF₃)₃

Cited by 73 publications

References 40 publications

Coordinative Properties of Highly Fluorinated Solvents with Amino and Ether Groups

Coordinative Properties of Highly Fluorinated Solvents with Amino and Ether Groups

Phase and redox shifted four iron/four sulfur clusters: fluorous analogs of metalloenzyme cofactors

Enhanced Hydrogenation Activity and Recycling of Cationic Rhodium Diphosphine Complexes through the Use of Highly Fluorous and Weakly‐Coordinating Tetraphenylborate Anions

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