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Dichlorotoluene
Dichlorotoluenes are organochlorine compounds, in particular aryl chlorides, with the formula . Six constitutional isomers exist, differing in the relative position of the two chlorine substituents around the ring. They are all colorless and lipophilic. The 3,5 isomer is a solid at room temperature, whereas the others are liquids. Preparation and uses Several dichlorotoluenes are prepared by treatment of toluene or monochlorotoluenes with chlorine in the presence of various Lewis acids. Purification is challenging because the individual isomers have similar properties. The 2,6 and 3,5 isomers do not form acceptably from toluene or chlorotoluenes, so these isomers are prepared by indirect methods. For example, 2,6-dichlorotoluene can be prepared by chlorination of P-toluenesulfonyl chloride, 4-toluenesulfonyl chloride followed by desulfonation. Some dichlorotoluenes are precursors to commercial pesticides. 2,4-Dichlorotoluene is the precursor to pyrifenox, butafenacil, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichlobenil
2,6-Dichlorobenzonitrile (DCBN or dichlobenil) is an organic compound with the chemical formula C6H3Cl2CN. It is a white solid soluble in organic solvents. It is widely used as a herbicide and organic chemistry building block.Franz Müller and Arnold P. Applebyki "Weed Control, 2. Individual Herbicides" in Ullmann's Encyclopedia of Industrial Chemistry 2010 Mechanism of action It has herbicidal properties killing young seedlings of both monocot and dicot species. DCBN interferes with cellulose synthesis. DCBN adapted cell walls use minimal amounts of cellulose, instead relying on Ca2+-bridge pectates. Dichlobenil kills the roots of many species, but not all; further, the killing does not extend much beyond the portion actually soaked, according to the Californian department of agriculture in 1971. Application In 1996, the University of California reported that "dosages were difficult to control... and as a result soaking or spraying methods are no longer used. ... The curren ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorotoluene
Chlorotoluenes are aryl chlorides based on toluene in which at least one aromatic hydrogen atom is replaced with a chlorine atom. They have the general formula C7H8–''n''Cl''n'', where ''n'' = 1–5 is the number of chlorine atoms. Monochlorotoluene Monochlorotoluenes are chlorotoluenes containing one chlorine atom. There are three isomers, each with the formula C7H7Cl. Properties The isomers differ in the location of the chlorine, but have the same chemical formula. All have very similar boiling points, although ''p''-chlorotoluene has a much higher melting point due to a more tightly packed crystal structure. Benzyl chloride is an isomer, which has a chlorine substituted for one of the hydrogens of toluene's methyl group, and it is sometimes named α-chlorotoluene. Preparation A laboratory route to 2- and 4-chlorotoluene proceeds from 2- and 4-toluidines (i.e. 2- and 4-aminotoluene). These compounds are diazotization, diazotized followed by treatment with cuprous chlo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organochlorine Compounds
Organochlorine chemistry is concerned with the properties of organochlorine compounds, or organochlorides, organic compounds that contain one or more carbon–chlorine bonds. The chloroalkane class (alkanes with one or more hydrogens substituted by chlorine) includes common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with TCDD being one of the most notorious. Organochlorides such as trichloroethylene, tetrachloroethylene, dichloromethane and chloroform are commonly used as solvents and are referred to as "chlorinated solvents". Physical and chemical properties Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than water due to the higher atomic weight of chlorine versus hydrogen. They have higher b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toluenes
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon with the chemical formula , often abbreviated as , where Ph stands for the phenyl group. It is a colorless, water-insoluble liquid with the odor associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) attached to a phenyl group by a single bond. As such, its systematic IUPAC name is methylbenzene. Toluene is predominantly used as an industrial feedstock and a solvent. As the solvent in some types of paint thinner, permanent markers, contact cement and certain types of glue, toluene is sometimes used as a recreational inhalant and has the potential of causing severe neurological harm. History The compound was first isolated in 1837 through a distillation of pine oil by Pierre Joseph Pelletier and Filip Neriusz Walter, who named it ''rétinnaphte''. In 1841, Henri Étienne Sainte-Claire Deville isolated a hydrocarbon from balsam of Tolu (an aro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichlorotoluene
Trichlorotoluenes are organochlorine compounds, in particular aryl chlorides, with the formula . Six constitutional isomers exist, differing in the relative position of the three chlorine substituents around the ring. All isomers colorless and lipophilic solids. Preparation and use Four trichlorotoluenes—the 2,3,4-, 2,3,6-, 2,4,5-, and 2,4,6- isomers—are produced in significant yields by treatment of toluene with three equivalent (chemistry), equivalents of chlorine in the presence of various Lewis acids. These isomers result from the usual regioselectivity, selectivity of electrophilic aromatic substitution reactions of substituted benzenes. 2,3,6-Trichlorotoluene is a precursor to 2,3,6-trichlorobenzoic acid (2,3,6-TBA), a commercial herbicide. Related compounds * Dichlorotoluene References {{Reflist Toluenes Chlorobenzene derivatives Multiple compounds, tabular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzal Chloride
Benzal chloride is an organic compound with the formula C6H5CHCl2. This colourless liquid is a lachrymator and is used as a building block in organic synthesis. Preparation and usage Benzal chloride is produced by the free radical chlorination of toluene, being preceded in the process by benzyl chloride (C6H5CH2Cl) and followed by benzotrichloride (C6H5CCl3): : C6H5CH3 + Cl2 → C6H5CH2Cl + HCl : C6H5CH2Cl + Cl2 → C6H5CHCl2 + HCl : C6H5CHCl2 + Cl2 → C6H5CCl3 + HCl Benzylic halides are typically strong alkylating agents, and for this reason benzal chloride is treated as a hazardous compound. Treatment of benzal chloride with sodium gives stilbene. Most benzal chloride main industrial use is as a precursor to benzaldehyde. This conversion involves hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzonitrile
Benzonitrile is the chemical compound with the formula , abbreviated PhCN. This aromatic organic compound is a colorless liquid with a cherry or almond like odour. It is mainly used industrially to produce the melamine resin precursor benzoguanamine. Production and reactions It is prepared by ammoxidation of toluene, that is its reaction with ammonia and oxygen (or air) at . : + 3/2 + → + In the laboratory it can be prepared by the dehydration of benzamide or benzaldehyde oxime or by the Rosenmund–von Braun reaction using cuprous cyanide or NaCN/ DMSO and bromobenzene. : Hydrogenation of benzonitrile in principle gives benzylamine, but owing to transamination, dibenzylamine and tribenzylamine are also produced. Applications Laboratory uses Benzonitrile is a useful solvent and a versatile precursor to many derivatives. It reacts with amines to afford N-substituted benzamides after hydrolysis. It is a precursor to diphenylmethanimine via reaction with phen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butafenacil
Butafenacil is the International Organization for Standardization, ISO trivial name, common name for an organic compound of the pyrimidinedione chemical class used as an herbicide. It acts by enzyme inhibitor, inhibiting the enzyme protoporphyrinogen oxidase to control broadleaf and some grass weeds in crops including cereals and Rapeseed, canola. History In 1985, chemists at the Dr. R. Maag subsidiary of Hoffmann-La Roche filed patents for uracil derivatives which had herbicidal activity. In 1990 the agrochemical interests of Maag were sold to Ciba-Geigy and work continued to optimise this area of biological activity. By 1993 a patent claiming specific ester derivatives including butafenacil was published. This was developed for the market under the code number CGA276854 and launched in 2001. By that time, further mergers in the industry meant that the product was supplied by Syngenta with brand names including B Power. Synthesis As described in the Ciba-Geigy patent, the key st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
