Ionic liquid containing allylsulfonate anion
View Patent ↗Problem: Providing a novel ionic liquid, which is low-cost, environment-friendly, and has low viscosity and melting point. Means for Solving the Problem: The present invention is the invention of the ionic liquid represented by the general formula [1]: {wherein, R 1 to R 3 and n pieces of R 4 each independently represent hydrogen atom or alkyl group having 1 to 4 carbon atoms, R 5 to R 7 each independently represent alkyl group, aralkyl group, or aryl group, R 8 represents alkyl group, aralkyl group, aryl group, or the one represented by the general formula [2]: (wherein T represents alkylene chain having 1 to 8 carbon atoms, n represents 1 or 2, and R 1 to R 7 are the same as the above-described), X represents nitrogen atom or phosphorus atom, n represents 1 or 2. When n is 1, R 3 and R 4 are bound and may form cyclohexene ring together with the adjacent carbon atoms. In addition, when X is nitrogen atom, R 5 to R 7 or R 5 to R 6 may form hetero ring with nitrogen atom binding thereto}.
1. An ionic liquid of formula [1]:
wherein
R 1 to R 3 and n number of R 4 are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,
R 5 to R 7 are each independently an alkyl group optionally substituted with a hydroxyl group or an alkoxy group, an aralkyl group, or an aryl group,
R 8 is an alkyl group optionally substituted with a hydroxy group or an alkoxy group, an aralkyl group, an aryl group, or a group of formula [2]:
wherein
T is an alkylene chain having 1 to 8 carbon atoms,
n is 1 or 2, and
R 1 to R 7 are the same as above,
X is a nitrogen atom or a phosphorus atom,
n is 1 or 2, and
when n is 1, R 3 and R 4 may be bound together with the adjacent carbon atoms to form a cyclohexene ring,
when X is a nitrogen atom, R 5 to R 7 or R 5 to R 6 may form a hetero ring with the nitrogen atom binding thereto, and
when R 8 is a group of formula [2], X is a nitrogen atom.
2. The ionic liquid according to claim 1 , wherein the ionic liquid is of formula [3]:
wherein
R 9 is an alkyl group optionally substituted with a hydroxy group or an alkoxy group, an aralkyl group or an aryl group, and
R 1 to R 7 , X and n are the same as above, or the ionic liquid is of formula [4]:
wherein R 1 to R 7 , T and n are the same as above.
3. The ionic liquid according to claim 2 , wherein the anion in formula [3] or [4] is allylsulfonate or 2-methylallylsulfonate.
4. The ionic liquid according to claim 2 , wherein the cation in formula [3] is of one of formula [5] to [8] and [10] to [12]:
wherein
R 10 to R 11 and R 15 to R 17 are each independently a hydrogen atom, an alkyl group, or an aralkyl group,
R 12 to R 14 are each independently a hydrogen atom, an alkyl group, an aralkyl group, or an alkoxy group,
k is an integer of 0 to 5,
m is an integer of 0 to 10,
p and q are integers of 0 to 8, and
R 5 to R 7 and R 9 are the same as above.
5. The ionic liquid according to claim 2 , wherein the cation in formula [4] is of formula [13] or formula [14]:
wherein R 10 to R 12 , T, and k are the same as above.
6. The ionic liquid according to claim 1 , wherein the ionic liquid of formula [1] is 1-ethyl-4-methoxypyridinium allylsulfonate, 1-ethyl-3-methylimidazolium allylsulfonate, 1-propyl-3-methylimidazolium allylsulfonate, 1-isopropyl-3-methylimidazolium allylsulfonate, 1-butyl-3-methylimidazolium allylsulfonate, 1-allyl-3-methylimidazolium allylsulfonate, 1-allyl-3-ethylimidazolium allylsulfonate, 1-allyl-3-butylimidazolium allylsulfonate, 1-ethyl-1-methylpyrrolidinium allylsulfonate, or 1-(hydroxyethyl)-1-methylpiperidinium allylsulfonate.