Synthesis of agrochemicals

Oxalyl Chloride. This diacid chloride [79-37-8], ClCOCOCl, mol wt 126.9, is produced by the reaction of anhydrous oxaUc acid and phosphoms pentachloride. The compound vigorously reacts with water, alcohols, and amines, and is employed for the synthesis of agrochemicals, pharmaceuticals, and fine chemicals. 

The chlorophenols make up an important class of industrial chemical compounds. They are used as either intermediates in the synthesis of agrochemicals, dyestuffs, and pharmaceuticals or direcdy in formulations. 

Petroski RJ, Weisleder D (2002) ACS Symposium Series 800 (Synthesis of Agrochemicals VI) 231... 

Aniline is the parent compound of the aromatic amines, which are used in the synthesis of agrochemicals, dyes, and pharmaceuticals. There is a concern that aromatic amines may be released into the environment during production processes or incomplete treatment of industrial waste streams. Additiondly, aromatic amines can enter the environment from the reduction of azo dyes, polynitroaromatic munitions (e.g. TNT), and dinitro herbicides, and from hydrolytic degradation of several classes of pesticides, including the phenylurea, phenylcarbamate, and acylanilide herbicides. 

Fluorinated arenes are widely used as precursors for synthesis of agrochemicals and pharmaceuticals [71] with a volume of several thousand tons per year [72]. More than 20 % of the pharmaceuticals currently in clinical testing contain fluorinated aromatic substructures, for some types of agrochemical the proportion is even exceeding 50% for newly introduced compounds. 

Industry is very interested in chiral cyanohydrins because they are valuable starting materials for several classes of polyfunctional molecules that are useful in the synthesis of agrochemicals and pharmaceuticals. By use of a chiral catalyst the pro-chiral aldehydes or ketones, a large number of which are readily available, are... 

A excellent illustration of the practical application of this knowledge in the field of fine chemicals is in the production of 1,3,5-alkylbenzenes. Trialkylbenzenes such as 1,3,5-triisopropylbenzene are useful as high-temperature solvents and as starting materials for the synthesis of agrochemicals. 1,3,5-Triethylbenzene is a useful starting material for the synthesis of K-resins. 

Optically active amines are important intermediates and chiral auxiliaries in the technical synthesis of agrochemicals and pharmaceuticals. BASF, one of the world s leading producers of chiral amines, developed a process based on the enzymatic resolution of racemic amines 49 with Burkholderia plantarii lipase immobilized on polyacrylate (Scheme 16) [75,76]. Methoxyacetic acid estars are particularly well suited for the stereospecific enzymatic differentiation, giving both the free amine (S)-49 and the acylated product R)-50 in high ee. The reaction stops at 50% conversion and the selectivity factor was calculated to be as high as 500. A plug-flow or batch reactor can be used for the enzymatic reaction and the residence time is in the range of 5-7 h. The more important amine (R)-49 can be liberated with the aid of base and is subsequently purified by distil-... 

Suitable monomers are summarized in Table 9.1. 1,2,4-Triazole is a white to pale yellow solid with a melting point of 120°C. Synonyms are pyrrodiazole, IH-1,2,4-triazole, and 5-triazole. This compound should not be confused with a sulfanilamide compound that is addressed as triazole. In contrast to a triazole, a triazin refers to a 6-membered ring with three nitrogen atoms. 1,2,4-Triazole is used for the synthesis of agrochemicals, pharmaceutical substances, hydraulic fluids, and photochemical products. Both 1,2,4-triazole and 1,2,4-triazole are effective solvents for proton conducting electrol54es." ... 

Isonicotinonitrile (4-cyanopyridine, 4CP) ean be obtained by the am-moxidation of 4-picoline. It is mainly used in the preparation of Isoniazid, an antitubercular dmg and for the production of 4-dimethylaminopyridine (DMAP). The latter is generally used as an acylation catalyst for the synthesis of agrochemicals, pharmaceuticals and polymers. Vertellus is the largest producer of 4CP. The Chengdu XiYa Chemieal Technology Co. and Shanghai Boyle Chemical Co. China, Tokyo Chemical Industry Co. Japan, DKSH, Switzerland, Vertellus Specialties UK (formerly Seal Sands Chemicals Ltd.) are major global suppliers of 4CP. 2-Cyanopyridine (2CP) can be manufactured in the same way by ammoxidation of 2-picoline. However its application is limited and thus, production amounts are very low only. 

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