Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acids and salts thereof
Reexamination Certificate
1999-12-02
2001-07-31
Killos, Paul J. (Department: 1623)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acids and salts thereof
C560S103000, C562S493000
Reexamination Certificate
active
06268527
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing benzoic acid derivatives, each having at least two trifluoromethyl groups on the benzene ring, which are useful as intermediates of medicines, agricultural chemicals and various functional materials, and a novel compound obtained by this method.
Japanese Patent First Publication JP-A-64-47 discloses a method for producing a carboxylic acid. In this method, an organic chloride having at least one chlorine atom on its ring is reacted with carbon monoxide at a temperature of 150-300° C. in the presence of a base, using a palladium compound and a phosphine compound (e.g., bis(diphenylphosphino)butane) as catalysts.
Bull. Soc. Chim. France (1962) 587-93 discloses a method for producing 3,5-bis(trifluoromethyl)benzoic acid from 3,5-bis(trifluoromethyl)bromobenzene by Grignard reaction.
JP-A-9-67297 discloses a method for producing 3,5-bis(trifluoromethyl)benzoic acid and its ester. In this method, a starting material, 3,5-bis(trifluoromethyl)bromobenzene, is reacted with carbon monoxide and water or methanol in the presence of triethylamine and a catalyst that is a combination of palladium acetate and triphenylphosphine.
SUMMARY OF THE INVENTION
It is possible to obtain 3,5-bis(trifluoromethyl)benzoic acid and its ester with relatively good selectivity and yield by the method of JP-A-9-67297. In this method, however, some of the palladium may deposit in the form of palladium black, when it is started to introduce carbon monoxide into the reaction system. This may result in the actual decrease of the catalyst concentration. Therefore, it may be necessary to use a relatively large amount of the palladium compound. In the reaction of this publication, the halogen atom on the benzene ring of the starting material may be replaced with hydrogen atom, thereby producing a by-product. With this, the yield may become inferior. Furthermore, it may be difficult to separate such by-product from the aimed product.
It is therefore an object of the present invention to provide a method for producing a bis(trifluoromethyl)benzoic acid derivative in an easy, efficient way.
It is another object of the present invention to provide a novel bis(trifluoromethyl)benzoic acid derivative.
According to the present invention, there is provided a method for producing a benzoic acid derivative represented by the general formula (1). This method comprises reacting an aromatic compound represented by the general formula (2), with carbon monoxide and a hydroxy compound represented by the general formula (3), in the presence of (a) a metal compound containing a metal of 8, 9 and 10 groups of periodic table, (b) a first phosphine derivative represented by the general formula (4), and (c) a base,
where R is trifluoromethyl group, trifluoromethyloxy group, a halogen that is fluorine, chlorine, bromine or iodine, nitro group, acetyl group, cyano group, an alkyl group having a carbon atom number of 1-4, an alkoxyl group having a carbon atom number of 1-4, or an alkoxycarbonyl group having a carbon atom number of 2-5; R
2
is hydrogen or an alkyl group having a carbon atom number of 1-10; and n is an integer of 0-3,
where X is a halogen as defined above, trifluoromethanesulfonate group, an alkylsulfonate group having a carbon atom number of 1-4, or a substituted or unsubstituted arylsulfonate group; and R and n are defined as above,
R
2
OH (3)
where R
2
is defined as above,
(R
1
)
2
P—Q—P(R
1
)
2
(4)
where each R
1
is independently phenyl group, o-methylphenyl group, m-methylphenyl group, or p-methylphenyl group; and Q is a bivalent group.
According to the present invention, there is provided a novel bis(trifluoromethyl)benzoic acid derivative, that is, 2-chloro-3,5-bis(trifluoromethyl)benzoic acid, made by the method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the invention, as will be clarified hereinafter, the yield and the selectivity can be remarkably improved by using a palladium compound as the above metal compound together with the above special phosphine derivative. Furthermore, it is possible to significantly reduce the deposition of the metal (e.g., palladium) by using as the metal compound the after-mentioned complex compound such as dichloro[1,4-butanediylbis(diphenylphosphine)P,P′]palladium, PdCl
2
(dppb).
As stated above, the aromatic compound, which is the starting material of the invention, is represented by the general formula (2). In this formula, R is not particularly limited as long as it is an inert substituent in the reaction. In fact, as mentioned above, R can be trifluoromethyl group, trifluoromethyloxy group, a halogen that is fluorine, chlorine, bromine or iodine, nitro group, acetyl group, cyano group, an alkyl group having a carbon atom number of 1-4, an alkoxyl group having a carbon atom number of 1-4, or an alkoxycarbonyl group having a carbon atom number of 2-5. Examples of the alkyl group are methyl group, ethyl group, n-propyl group, and i-propyl group. Examples of the alkoxyl group are methoxy group, ethoxy group, n-propoxy group, and i-propoxy group. Examples of the alkoxycarbonyl group are methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, and i-propoxycarbonyl group. In the general formula (2), X is the most preferably bromine or iodine in practice. Furthermore, R is preferably chlorine, bromine, or iodine in view of the usefulness of the reaction product as an intermediate in the field of fluorine chemistry.
In the invention, the aromatic compound is preferably a halogeno-bis(trifluoromethyl)benzene represented by the general formula (5),
where Y is bromine or iodine. This halogeno-bis(trifluoromethyl)benzene is not particularly limited. Its nonlimitative examples are
1-bromo-2,4-bis(trifluoromethyl)benzene,
1-iodo-2,4-bis(trifluoromethyl)benzene,
1-bromo-3,5-bis(trifluoromethyl)benzene
[3,5-bis(trifluoromethyl)bromobenzene],
1-iodo-3,5-bis(trifluoromethyl)benzene
[3,5-bis(trifluoromethyl)iodobenzene],
2-bromo-1,3-bis(trifluoromethyl)benzene,
2-iodo-1,3-bis(trifluoromethyl)benzene,
2-bromo-1,4-bis(trifluoromethyl)benzene,
2-iodo-1,4-bis(trifluoromethyl)benzene, and
4-bromo-1,2-bis(trifluoromethyl)benzene.
Similar to the halogeno-bis(trifluoromethyl)benzene, the aromatic compound, which is represented by the general formula (2) and has the substituent R, is also preferably used in the invention. Nonlimitative examples of such aromatic compound are 1-bromo-2,3,4-tris(trifluoromethyl)benzene, 1-bromo-2,4,5-tris(trifluoromethyl)benzene, 1-iodo-2,3,5-tris(trifluoromethyl)benzene, 1-iodo-2,4,5-tris(trifluoromethyl)benzene, 2-bromo-1,3,5-tris(trifluoromethyl)benzene, 5-bromo-1,2,3-tris(trifluoromethyl)benzene, 5-iodo-1,2,3-tris(trifluoromethyl)benzene, 2-iodo-1,3,4,5-tetrakis(trifluoromethyl)benzene, 1,2-dibromo-3,4,5-tris(trifluoromethyl)benzene, 1,3-dichloro-5-iodo-2,4-bis(trifluoromethyl)benzene, 1,2-dibromo-4,5-bis(trifluoromethyl)benzene, 1,4-dibromo-2,5-bis(trifluoromethyl)benzene, 1-bromo-2-chloro-3,5-bis(trifluoromethyl)benzene [2-chloro-3,5-bis(trifluoromethyl)bromobenzene], 1-bromo-2-methoxy-3,5-bis(trifluoromethyl)benzene, 1-iodo-2-methoxy-3,5-bis(trifluoromethyl)benzene, 2-bromo-1-iodo-3,5-bis(trifluoromethyl)benzene, 2-bromo-1-nitro-3,5-bis(trifluoromethyl)benzene, 2-bromo-3,4-dichloro-1,5-bis(trifluoromethyl)benzene, and 5-bromo-2-chloro-1,3-bis(trifluoromethyl)benzene. Of the above examples of the aromatic compound, it is particularly preferable to use 3,5-bis(trifluoromethyl)bromobenzene or 3,5-bis(trifluoromethyl)iodobenzene. With this, it is possible to obtain a 3,5-bis(trifluoromethyl)benzoic acid derivative that is very useful. Furthermore, it is particularly preferable to use 2-chloro-3,5-bis(trifluoromethyl)bromobenzene as the aromatic compound. With this, it is possible to obtain 2-chloro-3,5-bis(trifluoromethyl)benzoic acid derivative that is also very useful.
As stated above, it is possible in the invention to obtain the benzoic acid derivative represented by the general fo
Hasegawa Seiji
Ishida Michio
Koide Makoto
Kume Takashi
Morino Yuzuru
Central Glass Company Limited
Crowell & Moring , L.L.P.
Killos Paul J.
LandOfFree
Method for producing benzoic acid derivatives does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for producing benzoic acid derivatives, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for producing benzoic acid derivatives will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2562158