Trichloromethane derivative

Starting from gem-bromochlorocyclopropanes 7, the corresponding chlorocyclo-propanes 8 are prepared without formation of bromocyclopropanes (Scheme 2.4) [14]. One of the chlorine atoms of the trichloromethane derivatives 9 is reduced to give the dichloromethane ones 10. Furthermore, methyl a-bromocinnamate is... 

Chlorination of various hydrocarbon feedstocks produces many usehil chlorinated solvents, intermediates, and chemical products. The chlorinated derivatives provide a primary method of upgrading the value of industrial chlorine. The principal chlorinated hydrocarbons produced industrially include chloromethane (methyl chloride), dichloromethane (methylene chloride), trichloromethane (chloroform), tetrachloromethane (carbon tetrachloride), chloroethene (vinyl chloride monomer, VCM), 1,1-dichloroethene (vinylidene chloride), 1,1,2-trichloroethene (trichloroethylene), 1,1,2,2-tetrachloroethene (perchloroethylene), mono- and dichloroben2enes, 1,1,1-trichloroethane (methyl chloroform), 1,1,2-trichloroethane, and 1,2-dichloroethane (ethylene dichloride [540-59-0], EDC). 

Where we have reason to suspect the involvement of a particular species as a labile intermediate in the course of a reaction, it may be possible to confirm our suspicions by introducing into the reaction mixture, with malice aforethought, a reactive species which we should expect our postulated intermediate to react with particularly readily. It may then be possible to divert the labile intermediate from the main reaction pathway—to trap it—and to isolate a stable species into which it has been unequivocally incorporated. Thus in the hydrolysis of trichloromethane with strong bases cf. p. 46), the highly electron-deficient dichlorocarbene, CClj, which has been suggested as a labile intermediate (p. 267), was trapped by introducing into the reaction mixture the electron-rich species cis but-2-ene (11), and then isolating the resultant stable cyclopropane derivative (12), whose formation can hardly be accounted for in any other way ... 

The earliest inhaled general anesthetic that found significant use is chloroform, CHCI3, more systematically trichloromethane, a simple derivative of methane. Chloroform was gradually replaced by diethyl ether, commonly known simply as ether, a safer and more effective molecule than chloroform. 

In view of the smooth addition of carbanions to the electrophilic P atom of phosphorins (see p. 78 and 66), Markl and Merz attempted the addition of carbenoids (carbenes ) by reacting dichloromethane, trichloromethane or dichloro-phenylmethane with potassium-tert-butoxide in the presence of 2.4.6-triphenyl-X -phosphorin 22 or 2.4.6-tri-tert-butyl-X -phosphorin 24. The desired bicyclocompound 7/5 or the X -phosphepin 116 were not obtained. Instead, benzene derivatives were formed by loss of a PCI fragment, the fate of which was not determined. Markl has proposed a mechanism in which intermediates 114,115 and 116 ZK invoked ... 

Chloroform and Derivatives Chloroform and Trichloromethane (called Chloroform or Trichlormethan in Ger), CHC13 mw 119.39, col liq having a heavy ethereal odor, fr p -63 5°, bp 61.3°, d 1.498 at 15°, vap press 100mm at 10.4°, vap d 4.12 miscible with many org solvs, such as ale, ben2, eth, CS2, oils chlorinated solvents forms azeotropes with w, methanol, ale hexane. 

Derivation Gamma-ray initiated reaction of bromo-trichloromethane with allyl bromide. 

Phosgene is potentially derivable from trichloromethane in contact with a wide variety of oxidising agents, and only selected systems are described in this Section. The early... 

Tervalent phosphorus acid derivatives are normally liquids or low-melting solids which can be purified by distillation, or sometimes by recrystallization from a non-polar solvent. Most are oxidized in contact with the atmosphere, and many are easily hydrolyzed, so they must be kept under an inert atmosphere (N2 or Ar) during all manipulations. Flasks should be predried and solvents dried and deoxygenated before use. Tervalent phosphorus acid derivatives are, with few exceptions, thermally stable and can be kept indefinitely in ampoules under an inert gas (many halophosphines dissolve stopcock grease and should not be kept in stoppered flasks for prolonged periods). Inert solvents are hydrocarbons, ethers and, for most compounds, dichloromethane, ethyl acetate and tertiary amines. Aminophosphines react vigorously with tetrachloromethane and slowly with trichloromethane, and most tervalent phosphorus acid derivatives are oxidized by dimethyl sulphoxide and react with alcohols. 

Chloroform Trichloromethane, CHCI3. Chloroform is a clear, colorless, volatile, nonflammable liquid with characteristic pungent smell. It is toxic and carcinogenic. Derived by chlorination of methane. Formerly used as an anesthetic, it is now used mainly as a solvent and in organic synthesis to manufacture fluorocarbon plastics and insecticides. 

Czirjak et al. (1987) analyzed 21 female patients with SSc. In eight of them, occupationally hazardous agents were considered trichloroethylene in one, organic solvents in six, and polyethylene and possibly its derivatives in the last. Another patient had been heavily exposed to trichloromethane during 13 years of work renovating carburetors in Israel (Tibon-Fisher et al. 1992). 

Chlorination of swimming-pool water results in the formation of many chlorinated products. The most frequent derivative is trichloromethane (chloroform) (Camman and Hiibner 1995). Combined with organic nitrogenous compounds (urea, creatinine) generated by swimmers (sweat, urine), active free chlorine produces combined chlorine compounds, such as chloramines, which are irritants. When residual free chlorine levels are lower than 0.3 mg/1, chloramines increase. To decrease chloramine irritant levels and dissociate trichloramines, it is necessary to add chlorine, to provide water renewal and to ensure good air... 

Ci-derivatives Trichloromethane Monochloromethane Tetrachloromethane Phosgene Hydrochloro-fluorocarbons Polytetrafluoroethylene (PTFE) Silicones, methylcellulose Industrial processes Polycarbonates, diisocyanates, polyurethanes... 

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