8 Commercial Production of Ionic Liquids
201
O
R 1
R 2
O
+
2 NH 3
NH
R 1
R 2
NH
NH
R 1
R 2
NH
+
O
H
R 3
N
H
N
R 1
R 2
R 3
O
R 1
R 2
O
+ 2 NH 3
+ O
H
R 3
H 2 N
R 4
N
N
R 1
R 2
R 3
R 4
+
HX
N
H
N
R 1
R 2
R 3
R 4 X
N
N
R 1
R 2
R 3
R 4
(1)
(2)
(3)
(4)
Scheme 8.3 Strategies to synthesize heterocycles: (1) Debus reaction [5], (2) Radziszewski reaction [6], (3) deprotonation/alkylation of the heterocycle, (4) synthesis of 1-methylimidazoles by
Arduengo et al. [7]
larger than methyl, they have to be synthesized on a larger scale. In principle, this
can be achieved by two different approaches. The first one is to perform a cyclization
reaction. Unfortunately, the yields of these reactions are sometimes comparably low.
In addition to that, the starting materials are sometimes expensive or are only available in small quantities. Therefore, in terms of costs, it may be easier and cheaper to
alkylate the corresponding deprotonated heterocycle (Scheme 8.3).
Task-Specific ILs (TSILs)
The beautiful concept of task-specific ionic liquids (TSILs) was introduced by Davis
in 2001 [8]. This effort led to numerous novel ionic liquids, but though they sometimes
have unique properties, it has not been reported that they have been produced on a
relevant commercial scale. In principle, a plethora of organic reactions can be applied
to create ionic liquids having functionalized groups in their side chains, but because
of the complexity of this issue, it is not possible to consider them in detail.
201
O
R 1
R 2
O
+
2 NH 3
NH
R 1
R 2
NH
NH
R 1
R 2
NH
+
O
H
R 3
N
H
N
R 1
R 2
R 3
O
R 1
R 2
O
+ 2 NH 3
+ O
H
R 3
H 2 N
R 4
N
N
R 1
R 2
R 3
R 4
+
HX
N
H
N
R 1
R 2
R 3
R 4 X
N
N
R 1
R 2
R 3
R 4
(1)
(2)
(3)
(4)
Scheme 8.3 Strategies to synthesize heterocycles: (1) Debus reaction [5], (2) Radziszewski reaction [6], (3) deprotonation/alkylation of the heterocycle, (4) synthesis of 1-methylimidazoles by
Arduengo et al. [7]
larger than methyl, they have to be synthesized on a larger scale. In principle, this
can be achieved by two different approaches. The first one is to perform a cyclization
reaction. Unfortunately, the yields of these reactions are sometimes comparably low.
In addition to that, the starting materials are sometimes expensive or are only available in small quantities. Therefore, in terms of costs, it may be easier and cheaper to
alkylate the corresponding deprotonated heterocycle (Scheme 8.3).
Task-Specific ILs (TSILs)
The beautiful concept of task-specific ionic liquids (TSILs) was introduced by Davis
in 2001 [8]. This effort led to numerous novel ionic liquids, but though they sometimes
have unique properties, it has not been reported that they have been produced on a
relevant commercial scale. In principle, a plethora of organic reactions can be applied
to create ionic liquids having functionalized groups in their side chains, but because
of the complexity of this issue, it is not possible to consider them in detail.