Synthesis of ionic liquids

• US 7,423,164 B2
• Filed: 12/31/2003
• Issued: 09/09/2008
• Est. Priority Date: 12/31/2003
• Status: Expired due to Fees

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Dai, Sheng, Luo, Huimin
• Primary Examiner(s): O SULLIVAN, PETER G
• Application Number:
  US10/749,450
• Publication Number:
  US 20060211871A1
• Time in Patent Office: 1,714 Days
• Field of Search: 564/82, 564/463, 556/14, 556/111, 549/353, 549/208
• US Class Current: 556/14
• CPC Class Codes: C07C 211/65 Metal complexes of amines
• CPC Class Codes: C07C 311/48 having nitrogen atoms of sulfonamide groups further bound to another hetero atom
• CPC Class Codes: C07F 1/005 without C-Metal linkages

Abstract

Ionic compounds which are liquids at room temperature are formed by the method of mixing a neutral organic liqand with the salt of a metal cation and its conjugate anion. The liquids are hydrophobic, conductive and stable and have uses as solvents and in electrochemical devices.

Claims

1. A liquid ionic compound comprising a cation which is a complex of a neutral ligand selected from the group consisting of alkyl amines and crown ethers with a metal ion selected from the group consisting of Na⁺, K⁺, Li⁺, Ca²⁺, Ag⁺, Zn²⁺, Cu²⁺, Cd²⁺, Ni²⁺, Hg²⁺, Co³⁺ and Fe³⁺ and an anion which is a conjugate anion of the metal ion, wherein said anion comprises sulfur or phosphorous.

2. An ionic compound according to claim 1 which is a liquid below 100°

C.

3. An ionic compound according to claim 2 which is a liquid at room temperature.

4. An ionic compound according to claim 1 which is electrically conductive in the absence of a solvent.

5. An ionic liquid according to claim 1 which is hydrophobic.

6. An ionic compound according to claim 1 wherein said neutral organic ligand is a crown ether.

7. An ionic compound according to claim 1 wherein said conjugate anion is bis(trifluoromethane)sulfonimide, boron trifluoride, nitrate, sulfate, phosphate, hexafluorophosphate and dicyananiide.

8. A method for forming a liquid ionic compound, the method comprising mixing a neutral ligand selected from the group consisting of organic alkyl amines and crown ethers with a metal ion selected from the group consisting of Na⁺, K⁺, Li⁺, Ca²⁺, Ag⁺, Zn²⁺, Cu²⁺, Cd²⁺, Ni²⁻

, Hg²⁺, Co³⁺and Fe₃₊and with the salt of a metal cation and its conjugate anion at room temperature.

9. A method according to claim 8 wherein said neutral organic ligand is a crown ether.

10. A method according to claim 9 wherein the metal cation is selected from the group consisting of sodium, potassium, lithium and calcium.

11. A method according to claim 8 wherein said metal cation is selected from the group consisting of silver, zinc, copper, cadmium, nickel, mercury and iron.

12. A method according to claim 8 wherein said conjugate anion is bis(trifluoromethane)sulfonimide, boron trifluoride, nitrate, sulfate, phosphate, hexafluorophosphate and dicyanamide.