Process for producing fluorinated alkylamine compound

Details Process for producing fluorinated alkylamine compound Process for producing fluorinated alkylamine compound

2002-06-14

2003-03-18

Davis, Brian (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Amino nitrogen containing

C564S482000

Reexamination Certificate

active

06534683

ABSTRACT:

This application is a Continuation of prior International Application PCT/JP00/08817, filed Dec. 13, 2000.
TECHNICAL FIELD
The present invention relates to a process for producing a fluorinated alkylamine represented by F(CF
2
)
n
(CH
2
)
m
NH
2
.
BACKGROUND ART
A fluorinated alkylamine compound represented by F(CF
2
)
n
(CH
2
)
m
NH
2
is a compound useful as a starting material for the synthesis of various organic compounds. Particularly, CF
3
CH
2
NH
2
is a compound which is important as e.g. an intermediate for the synthesis of pharmaceuticals and agricultural chemicals.
As a method for producing F(CF
2
)
n
(CH
2
)
m
NH
2
by reacting F(CF
2
)N(CH
2
)
m
X with NH
3
, (1) a method for producing CF
3
CH
2
NH
2
by reacting from 1 to 3 times by mol of NH
3
to CF
3
CH
2
X in the presence of an inert solvent such as anhydrous N-methylpyrrolidone or anhydrous glycol (U.S. Pat. No. 4,618,718), (2) a method for producing CF
3
CH
2
NH
2
by reacting CF
3
CH
2
Cl with concentrated aqueous ammonia, wherein from 1 to 3 times by mol of NH
3
is used relative to CF
3
CH
2
Cl (U.S. Pat. No. 2,348,321) or (3) a method for producing CF
3
CH
2
NH
2
by reacting CF
3
CH
2
Cl or CF
3
CH
2
Br with concentrated aqueous ammonia, wherein 6.5 times by mol of NH
3
is used relative to CF
2
CH
2
Cl or CF
3
CH
2
Br (Dickey et al, Ind. Eng. Chem., Vol. 48,209, 1956), is, for example, known.
However, in the method (1), the reaction is carried out under an industrially disadvantageous high reaction pressure (7 to 11 MPa), and it is disclosed that if the pressure is lowered, the yield of CF
3
CH
2
NH
2
decreases. Further, when a duplicate test was carried out in accordance with the method (1), a problem was observed such that a part of CF
3
CH
2
NH
2
was reacted with HX formed as a by-product, to form a halogenated salt (CF
3
CH
2
NH
2
•HX), whereby the yield of CF
3
CH
2
NH
2
decreased (to a level of from 70 to 87%). Further, in order to convert the formed CF
3
CH
2
NH
2
•HX to CF
3
CH
2
NH
2
for recovery, it is necessary to add an aqueous alkali solution and to carry out extraction with an organic solvent, followed by distillation for purification, thus leading to a problem that the number of process steps increases, and the process becomes cumbersome. Further, there has been an additional problem that part of the formed CF
3
CH
2
NH
2
reacts with CF
3
CH
2
X to from a secondary amine compound represented by (CF
3
CH
2
)
2
NH or a tertiary amine compound represented by (CF
3
CH
2
)
3
N, whereby the yield of CF
3
CH
2
NH
2
tends to be low.
Further, in the method (2) or (3), no organic solvent is employed, and concentrated aqueous ammonia is used as a reaction solvent. CF
3
CH
2
X is hardly soluble in concentrated aqueous ammonia, whereby the reactivity with NH
3
tends to be low, and a problem that the yield tends to be low, was observed. Further, when the method (2) or (3) was practically employed, it was necessary to use an expensive reactor made of a corrosion resistant material such as hastelloy, since there was a problem of corrosion of the reactor.
DISCLOSURE OF THE INVENTION
The present invention has been made to solve the above problems and provides a process for producing a fluorinated alkylamine compound, which comprises reacting a compound represented by F(CF
2
)
n
(CH
2
)
m
X (wherein X represents a chlorine atom, a bromine atom or an iodine atom, and n and m each independently represents an integer of at least 1) with NH
3
to produce a compound represented by F(CF
2
)
n
(CH
2
)
m
NH
2
(wherein n and m have the same meanings as the above), and is characterized by conducting the reaction in the presence of a reaction solvent comprising an alkanediol as an essential component.
BEST MODE FOR CARRYING OUT THE INVENTION
In F(CF
2
)
n
(CH
2
)
m
X in the present invention, X is preferably a chlorine atom from the viewpoint of the availability, the reactivity, etc. Further, n is preferably from 1 to 16, more preferably from 1 to 8, particularly preferably 1. m is preferably from 1 to 10, more preferably from 1 to 5, particularly preferably 1. The following compounds may be mentioned as specific examples of F(CF
2
)
n
(CH
2
)
m
X.
CF
3
CH
2
Cl, CF
3
CH
2
Br, CF
3
CH
2
I, CF
3
CF
2
CH
2
Cl, CF
3
CF
2
CH
2
Br, CF
3
CF
2
CH
2
I, F(CF
2
)
3
CH
2
Cl, F(CF
2
)
4
CH
2
Cl, F(CF
2
)
5
CH
2
Cl, F(CF
2
)
6
CH
2
Cl, F(CF
2
)
7
CH
2
Cl, F(CF
2
)
8
CH
2
Cl.
CF
3
(CH
2
)
2
Cl, CF
3
(CH
2
)
2
Br, CF
3
(CH
2
)
2
I, CF
3
CF
2
(CH
2
)
2
Cl, CF
3
CF
2
(CH
2
)
2
Br, CF
3
CF
2
(CH
2
)
2
I, F(CF
2
)
3
(CH
2
)
2
Cl, F(CF
2
)
4
(CH
2
)
2
Cl, F(CF
2
)
5
(CH
2
)
2
Cl, F(CF
2
)
6
(CH
2
)
2
Cl, F(CF
2
)
7
(CH
2
)
2
Cl, F(CF
2
)
8
(CH
2
)
2
Cl.
CF
3
(CH
2
)
3
Cl, CF
3
(CH
2
)
3
Br, CF
3
(CH
2
)
3
I, CF
3
CF
2
(CH
2
)
3
Cl, CF
3
CF
2
(CH
2
)
3
Br, CF
3
CF
2
(CH
2
)
3
I, F(CF
2
)
4
(CH
2
)
3
Cl, F(CF
2
)
4
(CH
2
)
3
Cl, F(CF
2
)
5
(CH
2
)
3
Cl, F(CF
2
)
6
(CH
2
)
3
Cl, F(CF
2
)
7
(CH
2
)
3
Cl, F(C F
2
)
8
(CH
2
)
3
Cl.
In the present invention, at the time of reacting F(CF
2
)
n
(CH
2
)
m
X with NH
3
, a solvent comprising an alkanediol as an essential component, is used. As the alkanediol, a C
2-10
alkanediol is preferred for the reason of handling efficiency and the physical properties of the solvent. Further, as such an alkanediol, octane-1,8-diol, propylene glycol or ethylene glycol is preferred. Further, propylene glycol or ethylene glycol is particularly preferred, since the effects of the present invention are thereby distinctly observed.
Further, the reaction solvent preferably consists essentially of an alkanediol or essentially of an alkanediol and water. Particularly preferred is a reaction solvent consisting essentially of at least one member selected from propylene glycol and ethylene glycol, or a reaction solvent consisting essentially of at least one member selected from propylene glycol and ethylene glycol, and water. Especially preferred is a reaction solvent consisting of at least one member selected from propylene glycol and ethylene glycol. When water is present in the solvent, the total amount of the alkanediol is preferably at least 1 mass %, more preferably at least 10 mass %, relative to water.
The alkanediol is believed to have an activity to increase the solubility of F(CF
2
)
n
(CH
2
)
m
X and the reactivity of NH
3
with F(CF
2
)
n
(CH
2
)
m
X. If the proportion of the alkanediol in the reaction solvent becomes large, there will be an effect such that the yield of the fluorinated alkylamine compound will be remarkably high. Further, by using the alkanediol, F(CH
2
)
n
(CH
2
)
m
NH
2
will be formed in high yield even when the reaction pressure is adjusted to be low. Further, corrosion of the reactor can be prevented by using the alkanediol.
If the amount of the reaction solvent is too much, the volume efficiency of the reactor tends to be poor, and there will be a drawback that the productivity decreases. On the other hand, if the amount of the reaction solvent is too small, NH
3
and F(CF
2
)
n
(CH
2
)
m
X tend not to sufficiently be dissolved in the reaction solvent, whereby an industrially disadvantageous high reaction pressure will have to be used. Accordingly, the amount of the reaction solvent is preferably from 0.5 to 50 times by mass, more preferably from 1 to 20 times by mass, relative to F(CF
2
)
n
(CH
2
)
m
X.
In the present invention, at the time of reacting F(CF
2
)
n
(CH
2
)
m
X with NH
3
, it is preferred to employ at least 4 times by mol of NH
3
relative to F(CF
2
)
n
(CH
2
)
m
X. Namely, HX as a by-product (HX) in the reaction of F(CF
2
)
n
(CH
2
)
m
X with NH
3
, will further react with NH
3
to form NH
4
X, but if the amount of NH
3
is small, HX will also react with F(CF
2
)
n
(CH
2
)
m
NH
2
to form F(CF
2
)
n
(CH
2
)
m
NH
2
•HX. However, by adjusting the amount of NH
3
to be at least a certain specific level, the amount of formation of F(CF
2
)
n
(CH
2
)
m
NH
2
•HX can be remarkably reduced. This is considered to be such that excessively present NH
3
has a function to convert F(CF
2
)
n
(CH
2
)
m
NH
2
•HX to F(CF
2
)
n
(CH
2
)
m
NH
2
.
On the

Affiliated with

Also associated with

Rating

Process for producing fluorinated alkylamine compound does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for producing fluorinated alkylamine compound, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for producing fluorinated alkylamine compound will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3047276