Organic compounds -- part of the class 532-570 series – Organic compounds – Nitriles
Reexamination Certificate
1999-09-24
2002-08-13
Killos, Paul J. (Department: 1623)
Organic compounds -- part of the class 532-570 series
Organic compounds
Nitriles
C558S416000
Reexamination Certificate
active
06433211
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a process for producing cyanobenzoic acid derivatives, and more particularly, to a process for producing a cyanobenzoic acid compound, a cyanobenzamide compound, an alkyl cyanobenzoate compound, and a cyanobenzoyl chloride compound by use of a phthalonitrile compound as a raw material.
The cyanobenzoic acid compound, cyanobenzamide compound, alkyl cyanobenzoate compound, and cyanobenzoyl chloride compound which are produced through the process according to the present invention are useful intermediates for a variety of chemicals such as pharmaceuticals, agrochemicals, liquid crystals, and monomers for functional polymers.
BACKGROUND OF THE INVENTION
Firstly, conventional processes for producing a cyanobenzamide compound will be described.
A variety of methods for selectively converting one nitrile group of a phthalonitrile compound into an amide group are known. Examples thereof include (1) hydration in the presence of an acid catalyst; (2) hydration in the presence of a base catalyst; (3) reaction with hydrogen peroxide under basic conditions; (4) reaction of a nitrile group with a carbo cation; and (5) reaction of a nitrile group with an amine. However, these methods involve problems. For example, a phthalonitrile compound must be hydrated under strong acidic conditions due to the poor reactivity of the compound. Such acidic conditions induce corrosion of the material of the reactor used, for example. JP-A-52-39648 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”)and
J. Gen. Chem. USSR,
33, 631, (1963) disclose methods for selectively converting one nitrile group of a phthalonitrile compound into an amide group. The former method employs expensive sodium or potassium alkoxide, whereas the latter method discloses reaction of a terephthalonitrile compound with aqueous ammonia, the method requiring high temperature and high pressure and providing low selectivity. Thus, neither of these methods can serve as a low-cost process for producing a cyanobenzamide compound.
Collectionn Czechoslov. Chem. Commun.,
39, 2667, (1974) discloses reaction with hydrogen peroxide under basic conditions. The reaction has poor selectivity, to thereby produce a large amount of a phthalic diamide compound, and generates a large amount of oxygen. Thus, the method is industrially unsuitable. Reaction of a nitrile group with a carbocation or reaction of a nitrile group with an amine is primarily employed for synthesis of a secondary acid amide rather than synthesis of a cyanobenzamide compound. Other processes are employed for producing a cyanobenzamide compound by use of a phthalonitrile compound as a raw material. For example, JP-A-2-108655 discloses such a process involving reaction of terephthalonitrile and acetamide in the presence of palladium bromide, and
Synthesis,
12, 1034, (1984) discloses such a process involving reaction of terephthalonitrile and 2,2,6,6-tetramethylpiperidin-1-oxide. However, the former process has a poor yield and the latter process employs expensive materials. As described above, no known method is industrially advantageous for selectively converting one nitrile group of a phthalonitrile compound into an amide group.
Secondly, conventional processes for producing a cyanobenzoic acid compound will be described.
JP-A-64-47,
Dokl. Akad. Nauk. SSSR,
312, 5, 1129, (1990), and
J. Organomet. Chem.,
358, 1-3, 563, (1988) disclose processes involving reaction of a halobenzonitrile, such as chlorobenzonitrile, with carbon monoxide in the presence of a catalyst. SU 1,467,053 and
Azerv. Khim. Zh.,
1, 26, (1983) disclose processes involving oxidation of the methyl group of tolunitrile. U.S. Pat. No. 4,213,917 and WO 9009975 disclose processes involving oxidation of the aldehyde group of cyanobenzaldehyde. JP-A-50-71643 and JP-A-50-83346 disclose processes involving disproportionation between a nitrile and a carboxylic acid. These processes also involve problems. For example, raw materials are difficult to obtain or expensive, and severe conditions are required. Thus, these methods are not industrially advantageous and are insufficient as low-cost methods.
Among cyanobenzoic acid compounds, p-cyanobenzoic acid is synthesized in a classic manner; i.e., Sandmeyer's reaction in which p-aminobenzoic acid is diazotized and the diazo species is reacted with copper cyanide (Lucas et al.,
J. Am. Chem. Soc.,
51 (1929) 2718). Alternatively, processes for the synthesis involving oxidation of tolunitrile with a strong oxidizing agent such as chromic acid or permanganic acid (Levine et al.,
J. Org. Chem.,
24 (1959) 115; and Kattwinkel et al.,
Chem. Ber.,
37 (1904) 3226). These processes also involve problems. For example, Sandmeyer's reaction requires toxic copper cyanide; particularly, isolation and purification of p-cyanobenzoic acid under acidic conditions is difficult and dangerous due to generation of free hydrogen cyanide. Use of an oxidizing agent such as chromic acid or permanganic acid entails producing a toxic heavy metal waste as a by-product, which causes production of a large amount of toxic wastewater and thereby involves an environmental problem.
JP-A-61-85194 discloses that one nitrile group of terephthalonitrile is biologically hydrolyzed with an enzyme such as mononitrilase, to thereby synthesize p-cyanobenzoic acid. However, selectivity of hydrolysis of one nitrile group is poor, and hydrolysis must be carried out under low-concentration conditions, to thereby result in low productivity. In addition, by-products such as terephthalamic acid, terephthalamide, and terephthalic acid are inevitably produced along with the target p-cyanobenzoic acid.
Arkhipova et al.,
J. Gen. Chem. USSR,
33 (1963) 631 disclose a process involving hydrolysis of one nitrile group of terephthalonitrile with pressurized aqueous ammonia. It is reported that one nitrile group of terephthalonitrile is hydrated to form p-cyanobenzamide, and the amide group thereof is further hydrolyzed to form p-cyanobenzoic acid. However, the above hydrolysis requires high temperature and pressure and is not preferred, in consideration of safety.
As described above, conventionally known techniques for producing p-cyanobenzoic acid disadvantageously involve problems such as poor operational safety, formation of by-products, and difficulty in attaining production of high-purity compounds.
Thirdly, conventional processes for producing an alkyl cyanobenzoate compound will be described.
JP-A-58-113145 discloses a process involving reaction of carbon monoxide and an alcohol in the presence of chlorobenzonitrile serving as a catalyst.
Bull. Chem. Soc. Jpn.,
61, 6, 1985 (1988) and
J. Org. Chem.,
51, 24, 4714, (1986) disclose a process for producing methyl aminobenzoate involving Sandmeyer's reaction and a diazonium salt. JP-B-41-18818 (the term “JP-B” as used herein means an “examined Japanese patent publication”) discloses such a process involving disproportionation between a nitrile and an ester. The process employing carbon monoxide and the process involving Sandmeyer's reaction involve a raw material availability problem. The above disproportionation disadvantageously requires severe reaction conditions. Thus, no industrially advantageous and low-cost process for producing an alkyl cyanobenzoate compound has been known.
Fourthly, conventional processes for producing a cyanobenzoyl chloride compound will be described.
p-Cyanobenzoyl chloride is synthesized through reaction of p-cyanobenzoic acid with a chlorinating agent. Examples of chlorinating agents include thionyl chloride (JP-B-1-31501, Johan Kamphuis, et al.,
J. Chem. Soc. Perkin Trans.,
2 (1987) 907), oxalyl chloride (Robert J. Weikert, et al.,
J. Med. Chem.,
34 (1991) 1630), and phosphorus pentachloride (Raffaello Fusco, et al.,
Ann. Chim. (Rome),
42 (1952) 94). As an alternative to chlorination to produce an acid chloride, JP-A-63-313761 discloses a process involving reaction of 4-trichloromethylbenzamide in the presence of
Ito Haruaki
Marumo Kuniomi
Ohshiro Kimitaka
Saito Makoto
Soya Sumio
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