Ionic liquids and their use as solvents

A method of preparing an ionic compound, having a freezing point of up to 100° C., which method comprises reacting at least one amine salt of the formula

• R1R2R3R4N+X− (I)
• with at least one organic compound (II) which is capable of forming a hydrogen bond with X−, wherein R1, R2, R3 and R4 are each independently:-
• H,
• optionally substituted C1 to C5 alkyl,
• optionally substituted C6 to C10 cycloalkyl,
• optionally substituted C6 to C12 aryl,
• optionally substituted C7 to C12 alkaryl, or wherein
• R1 and R2 taken together represent a C4 to C10 optionally substituted alkylene group, thereby forming with the N atom of formula (I) a 5 to 11-membered heterocyclic ring, X− is NO3−, F−, Cl−, Br−, I−, BF4−, ClO4−, CN−, SO3CF3−, or COOCF3−, and wherein the term “optionally substituted” means that the group in question may or may not be substituted with one or more groups selected from OH, SH, SR5, Cl, Br, F, I, NH2, CN, NO2, COOR5, CHO, COR5 and OR5, wherein R5 is a C1 to C10 alkyl or cycloalkyl group,
• wherein all of R1, R2, R3 and R4 are not identical, and
• wherein compound (II) is a compound of the formula R6COOH, R7R8NH, R9CZNH2, or R10OH, wherein:-R6, R7, R8, R10 are each H, a C1–C8 alkyl group, an aryl group, or a C7–C12 alkaryl group optionally substituted with from 0 to 6 groups selected from OH, SR5, Cl, Br, F, I, NH2, CN, NO2, COOR5, COR5 and OR5, wherein R5 is H, a C1 to C10 alkyl or cycloalkyl group, R9 is a C1–C8 alkyl group, C1–C12 an aryl group, or a C7–C12 alkaryl group optionally substituted with from 0 to 6 groups selected from OH, SR5, Cl, Br, F, I, NH2, CN, NO2, COOR5, COR5 and OR5, wherein R5 is H, a C1 to C10 alkyl or cycloalkyl group, or wherein R9 is NHR11, wherein R11 is H or a C1–C6 alkyl group, and Z is O and wherein formula (I) and compound (II) have a molar ratio from 1:1.5 to 1:2.5.

A method of forming a solution of a solute, which method comprises dissolving the solute in an ionic compound having a freezing point of up to 100° C., the said ionic compound being formed by the reaction of at least one amine salt of the formula

• R1R2R3R4N+X− (I)
• with at least one organic compound (II) which is capable of forming a hydrogen bond with X−, wherein R1, R2, R3 and R4 are each independently:-
• H,
• optionally substituted C1 to C5 alkyl,
• optionally substituted C6 to C10 cycloalkyl,
• optionally substituted C6 to C12 aryl,
• optionally substituted C7 to C12 alkaryl, or wherein
• R1 and R2 taken together represent a C4 to C10 optionally substituted alkylene group, thereby forming with the N atom of formula (I) a 5 to 11-membered heterocyclic ring, X− is NO3−, F−, Cl−, Br−, I−, BF4−, ClO4−, CN−, SO3CF3−, or COOCF3−, and wherein the term “optionally substituted” means that the group in question may or may not be substituted with one or more groups selected from OH, SH, SR5, Cl, Br, F, I, NH2, CN, NO2, COOR5, CHO, COR5 and OR5, wherein R5 is a C1 to C10 alkyl or cycloalkyl group,
• wherein all of R1, R2, R3 and R4 are not identical, and
• wherein compound (II) is a compound of the formula R6COOH, R7R8NH, R9CZNH2, or R10OH, wherein:-R6, R7, R8, R10 are each H, a C1–C8 alkyl group, an aryl group, or a C7–C12 alkaryl group optionally substituted with from 0 to 6 groups selected from OH, SR5, Cl, Br, F, I, NH2, CN, NO2, COOR5, COR5 and OR5, wherein R5 is H, a C1 to C10 alkyl or cycloalkyl group, R9 is a C1–C8 alkyl group, C1–C12 an aryl group, or a C7–C12 alkaryl group optionally substituted with from 0 to 6 groups selected from OH, SR5, Cl, Br, F, I, NH2, CN, NO2, COOR5, COR5 and OR5, wherein R5 is H, a C1 to C10 alkyl or cycloalkyl group, or wherein R9 is NHR11, wherein R11 is H or a C1–C6 alkyl group, and Z is O and wherein formula (I) and compound (II) have a molar ratio from 1:1.5 to 1:2.5.