SULFONAMIDE MACROMOLECULES USEFUL AS SINGLE-ION CONDUCTING POLYMER ELECTROLYTE

Abstract

The present invention relates to asymmetric sulfonamide compounds comprising at least: one polycyclic group, Ar, formed of two to six rings, at least one of which is aromatic, a linear or branched, saturated or unsaturated aliphatic chain, said chain possibly being interrupted by one or more heteroatoms, said group Ar and said aliphatic chain being covalently bonded via a spacer represented by a sulfonamide unit SO.sub.2NH or its anionic form SO.sub.2N.sup.-; and, optionally a counter-cation of the anionic form of the sulfonamide unit, chosen among the alkali metals and the proton H.sup.+. These compounds are of particular interest as single-ion conducting polymer electrolyte.

Claims

1. An asymmetric sulfonamide compound comprising at least: a polycyclic group, Ar, consisting of two to six rings, at least one of which is aromatic, said rings each independently having from 4 to 6 members, said polycyclic group being able to include up to 18 heteroatoms; a linear or branched, saturated or unsaturated aliphatic chain, said chain being optionally interrupted by one or more heteroatoms, by one or more metalloids, optionally substituted by one or more fluorine atoms, and/or containing one or more groups selected from the group consisting of hydroxyl, NH.sub.2 and oxo groups, said aliphatic chain comprising a linear chain of at least six covalent bonds; said group Ar and said aliphatic chain being covalently linked via a spacer represented by a sulfonamide unit SO.sub.2NH or its anionic form SO.sub.2N.sup., said sulfonamide being linked to said polycyclic group Ar via its nitrogen atom and to said aliphatic chain via its sulfur atom; and, if need be a counter cation for the anionic form of the sulfonamide unit, selected from the alkali metals and the proton H.sup.+ or H.sub.3O.sup.+.

2. The compound of claim 1, wherein the compound is in the form of a salt having, as spacer, the anionic form of said sulfonamide SO.sub.2N.sup., and a counter cation.

3. The compound of claim 1, wherein the covalent bond between the nitrogen atom and said polycyclic group is established via an aromatic structure forming all or part of said polycyclic group.

4. The compound of claim 1, wherein said polycyclic group Ar is in a condensed aromatic form.

5. The compound of claim 1, wherein said polycyclic group Ar has one of the following polycyclic skeletons or is derived from one of the following polycyclic skeletons: ##STR00009##

6. The compound of claim 1, wherein said polycyclic group Ar is a radical derived from an aromatic bicyclic skeleton.

7-17. (canceled)

18. The compound of claim 1, wherein said polycyclic group Ar is a naphthalene radical.

19. The compound of claim 1, wherein the aliphatic chain is a linear alkyl chain including from 6 to 18 carbon atoms, optionally fluorinated, semifluorinated, or even perfluorinated, and/or optionally substituted by at least one or more hydroxyl group(s) and optionally intersected by one or more oxygen atom(s).

20. The compound of claim 1, wherein the aliphatic chain has an oligomeric, homopolymeric or copolymeric structure.

21. The compound of claim 1, wherein the aliphatic chain has a chain of at least 5 or more ethylene oxide units.

22. The compound having the general formula: ##STR00010## wherein Ar is a fully aromatic polycyclic group, R.sub.1 represents an aliphatic chain, and M.sup.+ is a counter cation selected from the group of alkali metals, as defined in claim 1.

23. The compound of claim 1 of formula ##STR00011##

24. A method of preparing an electrolyte, using the anionic form of an asymmetric sulfonamide compound comprising at least: a polycyclic group, Ar, consisting of two to six rings, at least one of which is aromatic, said rings each independently having from 4 to 6 members, said polycyclic group being able to include up to 18 heteroatoms; a linear or branched, saturated or unsaturated aliphatic chain, said chain being optionally interrupted by one or more heteroatoms, by one or more metalloids, optionally substituted by one or more fluorine atoms, and/or containing one or more groups selected from the group consisting of hydroxyl, NH.sub.2 and oxo groups; said group Ar and said aliphatic chain being covalently linked via a spacer represented by a sulfonamide unit SO.sub.2NH or its anionic form SO.sub.2N.sup.; and, if need be a counter cation for the anionic form of the sulfonamide unit, selected from the alkali metals and the proton H.sup.+ or H.sub.3O.sup.+.

25. The method of preparing an electrolyte using the anionic form of the asymmetric sulfonamide compound of claim 1.

26. An electrolyte formed wholly or partially by the anionic form of a compound of claim 1.

27. An electrochemical system comprising an electrolyte formed in whole or in part by the anionic form of an asymmetric sulfonamide compound comprising at least: a polycyclic group, Ar, consisting of two to six rings, at least one of which is aromatic, said rings each independently having from 4 to 6 members, said polycyclic group being able to include up to 18 heteroatoms; a linear or branched, saturated or unsaturated aliphatic chain, said chain being optionally interrupted by one or more heteroatoms, by one or more metalloids, optionally substituted by one or more fluorine atoms, and/or containing one or more groups selected from the group consisting of hydroxyl, NH.sub.2 and oxo groups; said group Ar and said aliphatic chain being covalently linked via a spacer represented by a sulfonamide unit SO.sub.2NH or its anionic form SO.sub.2N.sup.; and, if need be a counter cation for the anionic form of the sulfonamide unit, selected from the alkali metals and the proton H.sup.+ or H.sub.3O.sup.+.

28. An electrochemical system comprising an electrolyte formed in whole or in part by the anionic form of the asymmetric sulfonamide compound of claim 1.

29. The electrochemical system of claim 27, wherein the system is an electrochemical generator, converter or storage system.

30. The electrochemical system of claim 27, wherein the system is a proton exchange membrane fuel cell or redox flow battery, a primary or secondary battery, or a lithium-air or lithium-sulfur battery.

Description

[0102] The invention will now be described using the following examples and figures, submitted for illustrative and non-limiting purposes.

[0103] FIG. 1: Cyclic voltammetry (CV) diagram at 10 mV/s of the compound IA (example 1) in reduction mode (0.12 V to +0.90 V vs. Ag/Ag.sup.+).

[0104] FIG. 2: Cyclic voltammetry (CV) diagram at 10 mV/s of the compound IA (example 1) (in oxidation mode (0.00 V to 3.10 V vs. Ag/Ag.sup.+).

[0105] FIG. 3: 1H NMR spectrum (DMSO-d6, 400 MHz) of the compound IB

[0106] FIG. 4: Calorimetric analysis of the compound IB by DSC.

EXAMPLE 1

[0107] Synthesis of the Compounds IA and IB According to the Invention

[0108] Step a)

##STR00004##

[0109] An oven-dried round-bottom flask is loaded with 1-aminonaphthalene (1-AN, 3.70 g, 25.9 mmol, 1.10 equivalent) and pyridine (4 mL). To the slightly purple and stirred solution is added 1-octanesulfonyl chloride (1-OSC, 5 g, 23.5 mmol) in DCM (1 mL), dropwise at 0 C., for 15 minutes. The reaction is exothermic. When OSC is added, the solution first forms a light, lime green color, then becomes light and shiny magenta. The solution darkens over time. After stirring for 18 hours, the solution is acidified with HCl (2 M, 12 mL), inducing phase separation. The organic phase is diluted with DCM (20 mL), separated and then extracted again with HCl (2 M, 12 mL). The aqueous phase is extracted again with DCM (210 mL). The organic phases are combined, extracted with water and brine, then dried over MgSO.sub.4. The solvent is removed under vacuum to obtain the product. A single product is observed by TLC (1:1 MeOH/CHCl.sub.3 as eluent).

[0110] Yield=7.07 g, 22.1 mmol, 94.2%.

[0111] The purity of the sample was confirmed by .sup.1H NMR (DMSO-d6, 200 MHz), (ppm): NH 9.75, ArH (1H) 8.27, ArH (2H) 7.94, ArH (2H) 7.82, ArH (4H) 7.54, CH.sub.2SO.sub.2 3.09, CH.sub.2CH.sub.2SO.sub.2 1.69, CH.sub.2 (10H) 1.17, CH.sub.3 0.83.

[0112] Compound IA is characterized by cyclic voltammetry in oxidation and reduction.

[0113] The voltammogram (CV) of the compound IA (0.1 M in acetonitrile) in reduction (0.12 V to +0.90 V vs. Ag/Ag.sup.+), was measured at 10 mV/s (10 cycles) with a glassy carbon working electrode and a counter electrode with a larger glassy carbon surface area. The reference electrode consists of a silver wire immersed in a solution containing 0.01 M AgNO.sub.3 and 0.1 M tetraethylammonium tetrafluoroborate in acetonitrile.

[0114] The voltammogram (CV) of the compound IA (0.1 M in acetonitrile) in oxidation (0.00 V to 3.10 V vs. Ag/Ag.sup.+) was also measured at 10 mV/s (7 cycles) with a glassy carbon working electrode and a counter electrode with a larger glassy carbon surface area. The reference electrode also consists of a silver wire immersed in a solution containing 0.01 M AgNO.sub.3 and 0.1 M tetraethylammonium tetrafluoroborate in acetonitrile.

[0115] FIGS. 1 and 2 respectively show the resulting curves.

[0116] Compound I(A) is stable over an electrochemical window of [2.0 V-0.8 V] vs. Ag/Ag.sup.+. No significant oxidation waves are apparent (current <50 nA/cm.sup.2). A significant reduction current (>1 A/cm.sup.2) can be observed below 2.0 V vs. Ag/Ag.sup.+.

[0117] The lithium salt is then obtained as follows:

[0118] Step b)

##STR00005##

[0119] A dry flask is loaded with N-(naphthyl) octanesulfonamide 1 (0.508 g, 1.59 mmol) and CHCl.sub.3 (4 mL) and heated to 40 C. LiH is added slowly (75.8 mg, 9.54 mmol, 6 equivalents) to the stirred solution. The round-bottom flask is sealed and heated with shaking overnight. After 18 hours, MeOH (3 mL) is added dropwise to the reaction mixture. The solution is cooled to room temperature, concentrated under reduced pressure, then diluted with propan-2-ol. The resulting suspension is filtered under reduced pressure and the filtrate collected. Solvents are removed by rotary evaporation.

[0120] The resulting compound was analyzed by 1H NMR (see FIG. 3). The disappearance of the sulfonamide proton observed in the starting compound is noted.

[0121] Compound IB was characterized by differential scanning calorimetry (DSC) analysis under argon and with a heating rate of 5 C./min from 20 C. to 180 C. The rings are numbered 1, 2, 3.

[0122] The results are presented in FIG. 4.

[0123] Compound IB has an endotherm at about 20 C. and an exotherm at about 50 C., indicating reversible crystallization/melting over 3 cycles.

EXAMPLE 2

[0124] Synthesis of the Compound IC According to the Invention

[0125] Step a)

##STR00006##

[0126] A flask is loaded with a solution of methoxy-PEO-OH (Mn=500 g/mol, 5.00 g, 10 mmol of hydroxy end groups) and CBr.sub.4 (4.97 g, 15 mmol) in dichloromethane (DCM, 25 mL) and cooled to 0 C. To this clear colorless solution is added PPh.sub.3 (3.93 g, 15 mmol) in the form of a dry powder for 15 minutes at 0 C. The solution is allowed to warm up to room temperature and stirring continues overnight. The solution is then concentrated under reduced pressure and precipitated in cold heptane (175 mL) and pentane (320 mL). The solid is dried under reduced pressure, then taken up in diethyl ether and filtered. Diethyl ether is removed under reduced pressure to obtain the methoxy-PEO-Br product (580 g/mol) in the form of a light-yellow oil (4.26 g, 7.57 mmol, yield 75.7%).

[0127] Step b)

##STR00007##

[0128] A flask is loaded with methoxy-PEO-Br (580 g/mol, 1.00 g, 1.72 mmol) in MeCN (5 mL). The solution is stirred for 1 hour at room temperature. Potassium thioacetate (295 mg, 2.59 mmol, 1.5 equivalent) is added to the stirred mixture as a solution in MeCN (11 mL)/EtOH (2 mL). The reaction mixture is stirred at room temperature overnight and then concentrated under reduced pressure (109 to 115 mbar, 25 to 28 C.). EtOH (10 mL) is then added, followed by 2 M NaOH (2 mL, 4 mmol). The reaction medium is heated to reflux (100 C., 2 h) and then neutralized by adding 2 M HCl (2 mL, 4 mmol). Volatile compounds are removed under reduced pressure. The oily residue is taken up in DCM and filtered to obtain the crude product of methoxy-PEO-SH in the form of an oil.

[0129] Step c)

##STR00008##

[0130] A flask is loaded with methoxy-PEO-SH (500 mg, 516 g/mol, 0.97 mmol) in acetonitrile (MeCN, 10 mL) and deionized water (43.6 mg, 2.42 mmol, 2.5 equivalents) and cooled to 0 C. Tetrabutylammonium chloride (Bu.sub.4NCl, 1.077 g, 3.88 mmol, 4.0 equivalents) and N-chlorosuccinimide (NCS, 388 mg, 29.07 mmol, 3.0 equivalents) are then added and the reaction mixture is stirred at 0 C. for 1 hour. 1-Amino-naphthalene (305 mg, 2.122 mmol, 2.2 equivalents) is then added to the stirred mixture, which is then left at room temperature. The reaction mixture is stirred overnight. MeCN (10 mL) is added to dilute the mixture. The suspension is filtered and the precipitate washed with MeCN (410 mL). The solutions are combined and the solvent is removed under reduced pressure. The crude product is taken up in CHCl.sub.3 and passed through a silica gel column. The solvent is evaporated and the residue taken up in deionized water, treated with lithium hydroxide monohydrate up to a pH-metric turn and then extracted with CHCl.sub.3. The combined organic phases are then dried over K.sub.2CO.sub.3 and the solvent removed under reduced pressure to obtain the product in the form of a dark violet oil.