Chlorine transfer

On August 14, 2002, a 1-in chlorine transfer hose (CTH) used in a rail-car offloading operation at DPC Enterprises in Festus, Missouri, catastrophically ruptured and initiated a sequence of events that led to the release of 48,000 lb of chlorine into neighboring areas. The material of construction of the ruptured hose was incorrect. The distributor fabricated bulk CTH with Schedule 80 Monel 400 end fittings and a high-density polyethylene spiral guard. Three hoses were shipped directly to the Festus facility from the distributor two were put into service on June 15, 2002. The hose involved in the incident failed after 59 days in service. 

Pattison, D. I. and Davies, M. J. (2006). Evidence for rapid inter- and intramolecular chlorine transfer reactions of histamine and carnosine chloramines Implications for the prevention of hypochlorous-acid-mediated damage. Biochemistry 45, 8152-8162. 

Chlorine. Transfer a weighed portion of approx 5g of the dried sample to a filtering crucible equipped with a filter paper disc. Wash with two 25-ml pottions of distilled water at 90°— 100°C, catching the filtrate in a test tube. Add to the filtrate three drops of nitric acid (sp gr 1-4) and 10 drops of a 10% soln of silver nitrate. Compare the turbidity with that produced when... 

Libby RD, Beachy TM, Phipps AK (1996) Quantitating Direct Chlorine Transfer from Enzyme to Substrate in Chloroperoxidase-Catalyzed Reactions. J Biol Chem 271 21820... 

In the oxidation of Cr2+(aq) by IrCl -, there is evidence for the formation of a chloro-bridged intermediate, but no overall chlorine transfer takes place the products are Cr3+(aq) and IrCl -. Bridging does appear to assist the process of electron transfer, but ultimate atom transfer is not absolutely essential. 

Under this type of catalysis we may classify those reactions in which reversible electron transfer takes place. The electron to be transferred may be carried by an atom, and in such a case we speak about hydrogen or chlorine transfer and the like. While in the previous case the reaction was characterized by the development of a positive charge at the reactive centre, and we could speak about carbonium ions, in the present case the reaction centre is characterized by the presence of an unpaired spin, and we may speak about free radical reactions, taking into account the same precautions as previously. 

These redox reactions, in which oxygen transfer occurs, involve changes of two units in the oxidation numbers of reactant and product. One-electron redox reactions may occur with the transfer of a halogen. The reaction between Cr+2 and Fe 3, for example, is strongly catalyzed by added chloride ion and when chloride is added to the reaction mixture, the resultant Cr(III) is present as (BUO CrC 2. It might be suggested that Cl becomes attached to Cr+a after the redox has occurred, but this cannot be. In the first place, independent experiments show that under these conditions the reaction between Cr+3 and Cl is very slow second, chloride attachment after the redox has occurred would not explain the catalytic role of chloride. It is more likely that the reaction occurs via a chloride-bridge transition state, and that the redox is accomplished by a chlorine transfer ... 

The degree of simple diastereoselectivity (anti addition) is dependent on the rate of chlorine transfer, relative to the isomerization of the intermediate carbon radical through rotation around the C-2-C-T bond. The configuration of the diastereomer was assigned on the basis of the H-NMR spectra. This is corroborated by the kinetics of rearrangement to piperidine systems, which is faster for the unti -isomer. 

You know that certain atoms, such as magnesium and chlorine, transfer electrons from one atom to another, forming an ionic bond. However, the number of ionic compounds is quite small compared with the total number of known compounds. What type of bonding is found in all these other compounds that are not ionically bonded ... 

The a-chlorophosphonates are valuable intermediates that have applications in the synthesis of alkynes, chloroolefins, and 1,2-epoxyphosphonates. Tetrachloromethane seems to be the most widely used reagent in the electrophilic monochlorination of phosphonates, presumably because it gives very clean chlorine transfer and produces an easily removed byproduct (chloroform) (Scheme 3.27). Only leq of base (n-BuLi) is needed to achieve the two successive deprotonations. A large number of chloroalkenes, some of them showing interesting insecticidal properties, have been obtained in 27-87% yields by this method (Scheme 3.27). ... 

The reaction starts off with chlorine transfer to pentachlorocyclo-hexadiene 2 with 2,4,6-trichlorophenol to produce some 2,3,4,6-tetrachlorophenol and tetrachlorocyclohexadienone 2 (eqn. 25). 

According to Scheme 11, the heteroaromatic attack overcomes the very fast competitive chlorine-transfer from the N-chloroamine [(Eq. (9)] which is a step of the free-radical chain in the Hoffman-Loeffler i3) reaction... 

Scheme 14. Mechanism for metal-catalyzed chlorine transfer additions...

Scheme 15. Metal-catalyzed chlorine transfer cyclizations...

The titanium tetrachloride condenses as a liquid in the receiver and is colored yellow from dissolved chlorine. Transfer the liquid quickly to a glass-stoppered flask (which must be well dried) containing a few fine copper turnings, and leave it in contact with the copper overnight to allow the copper to react with the excess chlorine. Then decant the liquid into a small dry distilling flask, distill the liquid ( b.p. 136°), and collect and store the distillate in a glass-stoppered bottle. It can be used for Experiment 51 if desired. 

SO) similar treatment of the decahydronaphthalene (51) gave (52), which reacted with powdered potassium hydroxide at 150 °C to provide 3-ethyl-l,2,5,6-tetrafluoro-7-methylnaphthalene (53) (38%) plus (54) (27%) and (55) (25%). " The high reactivity of amine-co-ordinated copper(n) ions as chlorine-transfer agents is responsible for the excellent yield of the 1 1 adduct CCIs CHa CHCl [CFala CHiCHa (48) in experiments of the type covered by Scheme 18 replacement of the copper... 

The a-(alkylthio)ketones are dehydrogenated by phenylsulfenyl chloride (54). In this case chlorine transfer between the sulfur atoms of the reactants could be the initial and crucial step. There is little evidence asserting either a biphilic course or direct displacement at S during reaction of thiols with sulfenyl chlorides and acylsulfenyl chlorides (55). Both are soft interactions. 

Sulfoxides may be a-chlorinated by iodobenzene dichloride. Steps involving S-I bond formation, deprotonation, and internal chlorine transfer are postulated to account for the overall process (141). The iodine atom in the reagent plays the dual roles of an anchoring group as well as of an activator toward ylide generation. 

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