354 Agricultural chemicals

Global population growth is about 1.3% every year, and the population is expected to reach seven billion by 2015 and nine billion by 2050 [1], In the time it takes to read this sentence, another 20 people will have been added to the world s population [2], The number of malnourished people in the world has been estimated at 852 million. Each year, hunger and malnutrition are responsible for the deaths of six million children. In want of food, people plow forests and the world annually loses 9.4 million hectares of forests [3]. A hectare (ha) is 10,000 square meters and 9.4 million ha is about 36,000 square miles or about the size of the entire state of Indiana. Exacerbating the food problem is the use of crops as fuel. For example, in the United States, com is used to make ethanol for gasoline. In Brazil, sugar cane is used. There are other efforts to use crops such as soybean for biodiesel. It has been estimated that food production will have to increase 70% by 2050 to feed the growing population [4]. 

It takes about 11 years to bring a new agricultural chemical from discovery to the market and one estimate has the cost at about 200 million [5]. Another estimate is at an R D price tag of 265 million, with only one of 140,000 potential candidates making it to market [6]. The global agricultural chemicals market is about 38 billion [7]. 

Fundamentals of Industrial Chemistry Pharmaceuticals, Polymers, and Business, First Edition. John A. lyrell. 2014 John Wiley Sons, Inc. Published 2014 by John Wiley Sons, Inc. 

Miscellaneous (includes lube oil additives, copolymers, malic 31 

A number of chemicals contribute to this end use but malathion 1 accounts for half of the MA consumed in the agricultural chemicals.Among other popular derivatives of MA are maleic hydrazide, Captan and Difolatan, Endothal and Alar . Malathion 1 is an insecticide Maleic hydrazide 2 and Alar are herbicides and plant growth regulators Captan 4 and Difolatan 5 

Diels-Alder chemistry (see Chapter 4) is widely utilized for preparing agricultural chemicals. The versatility that MA can offer is best summarized in the quote it is a perfect molecule to make a pesticide because a wide variety of compounds can be made from it and it is environmentally acceptable.A review on biocides based on MA has been published recently.  

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In this chapter we examine in turn the properties of alkyl and aryl-thiazoles that do not possess functional groups bonded directly to the thiazole ring. The general trends are underlined, and the applications of certains thiazole compounds in such areas as polymers, flavorings, and pharmacological and agricultural chemicals are discussed. 

Tetrahydrofurfuryl alcohol also has been cleared for use in California under Rule 66. It meets the rigid specifications for uv degradation in environmentally sensitive areas. In addition to domestic use, a substantial amount of tetrahydrofurfuryl alcohol is used as a solvent for agricultural chemicals in Europe. 

Uses. Butanediol is used to manufacture the insecticide Endosulfan, other agricultural chemicals, and pyridoxine (vitamin B ) (see Vitamins) (116). Small amounts are consumed as a diol by the polymer industry. 

Uses. Butyrolactone is principally consumed by the manufacturers by reaction with methylamine or ammonia to produce A/-meth5d-2-pyrrohdinone [872-50-4] and 2-pyrrohdinone [616-45-5] C H NO, respectively. Considerable amounts are used as a solvent for agricultural chemicals and polymers, in dyeing and printing, and as an intermediate for various chemical syntheses. 

Glycol monoether CAS n R Agriculture Chemical Eoo Cleaning Textile Transport... 

W. T. TEom son, Agricultural Chemicals, Book III—Miscellaneous Agricultural Chemicals, 1991 —92 Revision, Thompson PubHcations, Eresno, Calif.,... 

W. T. TForsison, Agricultural Chemicals, Book II Herbicides, 1989—1990 rev., Thomson Pubhshers, Fresno, Calif., 1989. 

Other sources of by-product HCl include allyl chloride, chlorobenzenes, chlorinated paraffins, linear alkylbenzene, siHcone fluids and elastomers, magnesium, fluoropolymers, chlorotoluenes, benzyl chloride, potassium sulfate, and agricultural chemicals. 

Hydroxybenzaldehyde has extensive use as an intermediate in the synthesis of a variety of agricultural chemicals. Halogenation of Nhydroxybenzaldehyde, followed by conversion to the oxime, and subsequent dehydration results in the formation of 3,5-dihalo-4-hydroxybenzonitrile (2). Both the dibromo- and dhodo-compounds are commercially important contact herbicides, hromoxynil [1689-84-5] (2) where X = Br, and ioxynil [1689-83-4]( where X = I respectively (74). Several hydrazone derivatives have also been shown to be active herbicides (70). 

The second most important use of ketene is in the production of diketene [674-82-8] (3) by controUed dimeri2ation. Diketene has wide utility in the manufacture of pharmaceutical and agricultural chemicals, dyes, pigments and fine chemicals. 

Another large-volume use for organ olithium compounds is in the synthesis of pharmaceutical and agricultural chemicals, eg, antibiotics (qv), antihistamines, antidepressants, anticoagulants, vasodilators, tranquiU2ers, analgesics, fungicides, and pesticides (116—119). 

Maleic hydra2ide [123-33-1] (10) is one of a number of commercial agricultural chemicals derived from maleic anhydride. Maleic hydra2ide was first prepared ia 1895 (39) but about 60 years elapsed before the iatermediate products were elucidated (40). 

Devrinol, 2-(l-naphthoxy)-Al,A/-diethylpropionamide/7 i25 5 -5 5 -7/ (napropamide) (23), which is prepared from 1-naphthol, is used as a herbicide (61). Another agricultural chemical, 1-naphthoxyacetic 2Lcid[2976-75-2] (24), is prepared by stirring 1-naphthol with monochloroacetic acid and sodium hydroxide in water at 100—110°C for several minutes. After treatment with concentrated HCl about 94% of the product is obtained (62). 

Agricultural Chemicals. Many claims exist for the use of nickel chemicals as nematocides, miticides, and other pesticides (qv) (191). 

Uses. (9-Nitrochlorobenzene is used in the synthesis of azo dye intermediates such as o-chloroaniline (Fast YeUow G Base), i9-nitroani1ine (Fast Orange GR Base), o-anisidine (Fast Red BB Base), o-phenetidine, and (9-aminophenol (see Azo dyes). It also is used in corrosion inhibitors, pigments, and agriculture chemicals. -Nitrochlorobenzene is used principally in the production of intermediates for azo and sulfur dyes. Other uses include pharmaceuticals (qv), photochemicals, mbber chemicals (qv), and insecticides (see Insectcontroltechnology). Typical intermediates manufactured from the para isomer are -lutioaruline (Fast Red GC Base), anisidine, -aminophenol, -nitrophenol, -phenylenediamine, 2-chloro-/)-anisidine (Fast Red R Base), 2,4-dinitrochlorobenzene, and l,2-dichloro-4-nitrobenzene. 

Uses. (9-Nitrotoluene is used in the synthesis of intermediates for azo dyes, sulfur dyes, mbber chemicals, and agriculture chemicals. Typical intermediates are o-toluidine, o-nitrobenzaldehyde, 2-nitro-4-chlorotoluene, 2-nitro-6-chlorotoluene, 2-amino-4-chlorotoluene (Fast Scarlet TR Base), and 2-amino-6-chlorotoluene (Fast Red KB Base). -Nitrotoluene is used principally in the production of intermediates for azo and sulfur dyes. Typical intermediates are -toluidine, -nitrobenzaldehyde, and 4-nitro-2-chlorotoluene. 

Additioaal uses for higher olefias iaclude the productioa of epoxides for subsequeat coaversioa iato surface-active ageats, alkylatioa of benzene to produce drag-flow reducers, alkylation of phenol to produce antioxidants, oligomeriza tion to produce synthetic waxes (qv), and the production of linear mercaptans for use in agricultural chemicals and polymer stabilizers. Aluminum alkyls can be produced from a-olefias either by direct hydroalumination or by transalkylation. In addition, a number of heavy olefin streams and olefin or paraffin streams have been sulfated or sulfonated and used in the leather (qv) iadustry. 

NACA, From Fab to Fabeh The Kesearch Testing and Registration of A.gricultural Chemicals National Agricultural Chemicals Association, Washington, D.C., Feb. 1993. NACA became the American Crop Protection Association in late 1994. 

Much effort has been placed in the synthesis of compounds possessing a chiral center at the phosphoms atom, particularly three- and four-coordinate compounds such as tertiary phosphines, phosphine oxides, phosphonates, phosphinates, and phosphate esters (11). Some enantiomers are known to exhibit a variety of biological activities and are therefore of interest Oas agricultural chemicals, pharmaceuticals (qv), etc. Homochiral bisphosphines are commonly used in catalytic asymmetric syntheses providing good enantioselectivities (see also Nucleic acids). Excellent reviews of low coordinate (coordination numbers 1 and 2) phosphoms compounds are available (12). 

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