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PROCESS FOR THE PREPARATION OF CHLOROMETHYL TRIFLUOROACETATE
Field of the invention
The present invention provides a process for the preparation of chloromethyl
trifluoroacetate of Formula I.
Background of the invention
The chloromethyl trifluoroacetate is used as a key intermediate in the pharmaceutical
industry. Particularly, it is useful as a starting material for the preparation of methyl
fluoroacrylate, which is a key intermediate for agrochemicals and pharmaceuticals.
O CH2Cl
O
F
F
F
Formula I
The present invention provides a process of preparation of chloromethyl trifluoroacetate of
Formula I which is simple, economically viable and industrially doable.
Summary of the invention
The present invention provides a process for the preparation of a compound of Formula I,
comprising;
a) contacting a compound of Formula II with chlorine to obtain the compound of Formula
I; and
b) isolating the compound of Formula I from step a).
3
O CH2Cl
O
F
F
F
Formula I
O
CH3
O
F
F
F
Formula II
Detailed description of the invention
The present invention provides a process for the preparation of a compound of Formula I,
comprising;
a) contacting a compound of Formula II with chlorine to obtain the compound of Formula
I; and
b) isolating the compound of Formula I from step a).
O CH2Cl
O
F
F
F
Formula I
4
O
CH3
O
F
F
F
Formula II
The compound of Formula II may be reacted with chlorine at a temperature in the range of
30oC to 75oC.
The chlorination takes place in the presence of light source, in particular visible light or
ultraviolet light in a range of from 450 to 260 nm.
The compound of Formula II may be obtained commercially or can be prepared by any of
the methods known in the art, for example, as in the U.S. Patent no.4,730,082.
The isolation of the compound of Formula I is carried out by distillation, evaporation and
layer separation or mixture thereof.
The compound of Formula I, obtained by the process of the present invention has a purity
greater than about 98% by gas chromatography.
The methyl 2-fluoroacrylate prepared by using the compound of Formula I, wherein the
compound of Formula I is prepared according to the present invention.
While the present invention has been described in terms of its specific embodiments,
certain modifications and equivalents will be apparent to those skilled in the art and are
intended to be included within the scope of the present invention.
The following examples are given by way of illustration and therefore should not be
construed to limit the scope of the present invention.
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Examples
Example 1: Preparation of chloromethyl trifluoroacetate
Methyl trifluoro acetate (250g, 1.95 mole) was placed in a quartz tube fitted with a condenser, thermometer and a magnetic bead for agitation. Two 110 volt/ 275 watt sunlamps placed two inches from the reactor tube were used as light source. Chlorine gas (76.3g, 1.074moles) was fed into the tube through a sintered glass plate at the rate of 6 liter per hour. The temperature of the reaction mass was maintained at 40oC by external cooling. The reactor tube was provided with an outlet for the evolved hydrogen chloride. The crude material was distilled at a temperature of 74oC to 76oC to obtain the title compound (159g).
Yield (%): 91
Purity (%): 95 by gas chromatography

We claim:
1. A process for the preparation of a compound of Formula I, comprising;
a) contacting a compound of Formula II with chlorine to obtain the compound of Formula
I; and
b) isolating the compound of Formula I from step a).
O CH2Cl
O
F
F
F
Formula I
O
CH3
O
F
F
F
Formula II
2. The process as claimed in claim 1, wherein the compound of Formula II is reacted with
chlorine at a temperature in the range of 30oC to 75oC.
3. The process as claimed in claim 1, wherein the chlorination takes place in the presence
of light source, in particular visible light or ultraviolet light in a range of from 450 to 260
nm.
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4. The process as claimed in claim 1, wherein the compound of Formula I is isolated by method selected from distillation, evaporation and layer separation or mixture thereof.
5. The process as claimed in claim 1, wherein the compound of Formula I, obtained by the process of the present invention, has a purity greater than about 98% by gas chromatography.