# US 9,433,895 B2 · Reversible room-temperature ionic liquids

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,433,895 B2
- Document ID: US9433895B2
- Status: Granted
- Kind: B2
- Application number: 14/072,439
- Filed: 2013-11-05
- Published: 2014-05-01
- Granted: 2016-09-06
- Earliest claimed: 2007-01-29
- Assignees: Georgetown University
- Applicants: Georgetown University
- Inventors: Tao Yu; Richard G. Weiss; Taisuke Yamada; Mathew George
- Web page: https://patentgrep.com/patent/US9433895B2

## CPC

- B01D 53/62: Carbon oxides
- B01D 53/1493: {Selection of liquid materials for use as absorbents}
- C07C 213/08: by reactions not involving the formation of amino groups, hydroxy groups or etherified or esterified hydroxy groups
- C07C 257/14: having carbon atoms of amidino groups bound to acyclic carbon atoms
- C07C 271/02: Carbamic acids; Salts of carbamic acids (unsubstituted carbamic acid or salts thereof C01B21/12)
- C07C 319/20: by reactions not involving the formation of sulfide groups
- C07C 323/43: Y being a hetero atom
- C07D 487/04: Ortho-condensed systems
- B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28)
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)

## Abstract

One aspect of the present invention relates to salts that are room-temperature ionic liquids (RTILs), methods of making them, and methods of using them in connection with temporary or permanent gas sequestration. Another aspect of the present invention relates to a class of solvents which can be transformed into RTILs by exposure to a gas, and methods of using them in connection with temporary or permanent gas sequestration.

## Claims

### Claim 1

A salt represented by:
wherein
R9 is absent or represents one or more substituents attached to the ring, each of which is independently selected from the group consisting of H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —SC(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, and —(CH2)n—NH2;
z is zero or an integer in the range of 1 to 3;
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —SC(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —SC(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡R8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
Y represents independently for each occurrence O or S;
R8 represents independently for each occurrence —(CH2)n—CH3, cycloalkyl, aryl, or heteroaryl; and
n represents independently for each occurrence an integer in the range 1-10 inclusive.

### Claim 2 (depends on 1)

The salt of claim 1, wherein
R9 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, or —C(R8)3;
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, or —C(R8)3; and
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, or —C(R8)3.

### Claim 3 (depends on 1)

The salt of claim 1, wherein
R9 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3;
R5 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3; and
R6 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3.

### Claim 4 (depends on 1)

The salt of claim 1, wherein
R9 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3;
R5 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3;
R6 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3; and
Y is O.

### Claim 5

A salt represented by:
wherein
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
Y represents independently for each occurrence O or S;
R8 represents independently for each occurrence —(CH2)n—CH3, cycloalkyl, aryl, or heteroaryl; and
n represents independently for each occurrence an integer in the range 1-10 inclusive.

### Claim 6 (depends on 5)

The salt of claim 5, wherein
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, or —C(R8)3; and
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, or —C(R8)3.

### Claim 7 (depends on 5)

The salt of claim 5, wherein
R5 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3; and
R6 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3.

### Claim 8 (depends on 5)

The salt of claim 5, wherein
R5 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3;
R6 represents H, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, —(CH2)n—R8, —CH(R8)2, or —C(R8)3; and
Y is O.

### Claim 9

A method of preparing a salt, comprising the step of contacting a gas with a first compound and a second compound, wherein said first compound is represented by
wherein
R9 is absent or represents one or more substituents attached to the ring, each of which is independently selected from the group consisting of H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, and —(CH2)n—NH2;
R8 represents independently for each occurrence —(CH2)n—CH3, cycloalkyl, aryl, or heteroaryl;
n represents independently for each occurrence an integer in the range 1-10 inclusive;
z is zero or an integer in the range of 1 to 3; and
said second compound is represented by
wherein
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R8 represents independently for each occurrence —(CH2)n—CH3, cycloalkyl, aryl, or heteroaryl;
n represents independently for each occurrence an integer in the range 1-10 inclusive; and
said gas is represented by:
Y═X═Y
wherein
X represents C or N; and
Y represents independently for each occurrence O or S.

### Claim 10

A method comprising the step of contacting a first gas with an ionic liquid, thereby generating a second gas; wherein said ionic liquid is represented by:
wherein
said first gas is an inert gas;
said second gas is CO2 or CS2;
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
X represents C;
Y represents independently for each occurrence O or S;
R8 represents independently for each occurrence —(CH2)n—CH3, cycloalkyl, aryl, or heteroaryl;
R9 is absent or represents one or more substituents attached to the ring, each of which is independently selected from the group consisting of H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, and —(CH2)n—NH2;
z is zero or an integer in the range of 1 to 3; and
n represents independently for each occurrence an integer in the range 1-10 inclusive.

### Claim 11

A method of removing a gas from a mixture, comprising the step of contacting said mixture with a first compound and a second compound, wherein said first compound is represented by
wherein
R9 is absent or represents one or more substituents attached to the ring, each of which is independently selected from the group consisting of H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R8 represents independently for each occurrence —(CH2)n—CH3, cycloalkyl, aryl, or heteroaryl;
n represents independently for each occurrence an integer in the range 1-10 inclusive;
z is zero or an integer in the range of 1 to 3; and
said second compound is represented by
wherein
R5 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R6 represents H, halogen, alkyl, fluoroalkyl, cycloalkyl, heterocycloalkyl, alkenyl, cycloalkenyl, heterocycloalkenyl, alkynyl, aryl, heteroaryl, aralkyl, heteroaralkyl, —(CH2)n—R8, —OR8, —N(R8)2, —SR8, —C(═O)OR8, —OC(═O)R8, —NR8C(═O)R8, —C(═O)N(R8)2, —C(═O)SR8, —S C(═O)R8, —S(═O)R8, —S(═O)2R8, —S(═O)2OR8, —C(═O)R8, —C(═NR8)R8, —C(═S)R8, —C(R8)═C(R8)2, —C≡CR8, —CH(R8)2, —C(R8)3, or —(CH2)n—NH2;
R8 represents independently for each occurrence cycloalkyl, aryl, or heteroaryl;
n represents independently for each occurrence an integer in the range 1-10 inclusive; and
said gas is represented by:
Y═X═Y
wherein
X represents C or N; and
Y represents independently for each occurrence O or S.