Reaction with atomic chlorine

Langer, S., B. T. McGovney, and B. J. Finlayson-Pitts, The Dimethyl Sulfide Reaction with Atomic Chlorine and Its Implications for the Budget of Methyl Chloride, Geophys. Res. Lett., 23, 1661-1664 (1996). 

Canosa-Mas, C.E., J.M. Duffy, M.D. King, K.C. Thompson, and R.P. Wayne (2002), The atmospheric chemistry of methyl salicylate-reactions with atomic chlorine and with ozone, Atmos. Environ., 36, 2201-2205. 

It has been proposed that aromatic solvents, carbon disulfide, and sulfur dioxide form a complex with atomic chlorine and that this substantially modifies both its overall reactivity and the specificity of its reactions.126 For example, in reactions of Cl with aliphatic hydrocarbons, there is a dramatic increase in Ihe specificity for abstraction of tertiary or secondary over primary hydrogens in benzene as opposed to aliphatic solvents. At the same time, the overall rate constant for abstraction is reduced by up to two orders of magnitude in the aromatic solvent.1"6 The exact nature of the complex responsible for this effect, whether a ji-coinplex (24) or a chlorocyclohexadienyl radical (25), is not yet resolved.126- 22... 

Kurlo, M.J. and Knable, G.L. A kinetic investigation of the gas-phase reactions of atomic chlorine ( P) and hydroxyl (X with acetonitrile atmospheric significance and evidence of decreased reactivity between strong electrophiles, J. Phys. Chem., 88(15) 3305-3308, 1984. 

Stelson, A. W and J. H. Seinfeld, Chemical Mass Accounting of Uban Aerosol, Environ. Sci. Technol., 15, 671-679(1981). Stickel, R. E., J. M. Nicovich, S. Wang, Z. Zhao, and P. H. Wine, Kinetic and Mechanistic Study of the Reaction of Atomic Chlorine with Dimethyl Sulfide, J. Phys. Chem., 96, 9875-9883 (1992). Swartz, E J. Boniface, I. Tchertkov, O. V. Rattigan, D. V. Robinson, P. Davidovits, D. R. Worsnop, J. T. Jayne, and C. E. Kolb, Horizontal Bubble Train Apparatus for Heterogeneous Chemistry Studies Uptake of Gas-Phase Formaldehyde, Environ. Sci. Technol, 31, 2634-2641 (1997). 

Kaiser, E. W and T. J. Wallington, Comment on Inverse Kinetic Isotope Effect in the Reaction of Atomic Chlorine with C2H4 and C2D4, J. Phys. Chem. A, 102, 6054-6055 (1998). 

Nordmeyer, T., W. Wang, M. L. Ragains, B. J. Finlayson-Pitts, C. W. Spicer, and R. A. Plastridge, Unique Products of the Reaction of Isoprene with Atomic Chlorine Potential Markers of Chlorine Atom Chemistry, Geophys. Res. Lett, 24, 1615-1618 (1997). 

Stutz, J., M. J. Ezell, A. A. Ezell, and B. J. Finlayson-Pitts, Rate Constants and Kinetic Isotope Effects in the Reactions of Atomic Chlorine with n-Butane and Simple Alkenes at Room Temperature, J. Phys. Chem., 102, 8510-8519 (1998). 

However, with the recent recognition of the potential importance of atomic chlorine and bromine under certain conditions in the Arctic at polar sunrise (e.g., see Barrie et al., 1988 and Niki and Becker, 1993), the potential for BrO and CIO chemistry has been reconsidered. As described in Chapter 6 J.4, at polar sunrise there is a rapid loss of ground-level 03 that appears to be associated with reaction with atomic bromine and at the same time, there is evidence that chlorine atoms are playing a major role in the organic removal (Jobson et al., 1994). This is consistent with reactions of sea salt particles generating atomic bromine and chlorine, although the exact nature of the reactions and halogen atom precursors remains unknown. 

Shekel, R. E., J. M. Nicovich, S. Wang, Z. Zhao, and P. H. Wine, Kinetic and Mechanistic Study of the Reaction of Atomic Chlorine with Dimethyl Sulfide, J. Phys. Chem., 96, 9875-9883 (1992). 

Formation of C02 from C1C(0)02 may also occur by reaction with atomic oxygen (equation 85) or chlorine (equation 86). Furthermore, the chloroformylperoxy radical is reduced by nitric oxide (equation 87), like its fluorine analogue. However, the resulting chloroformyloxy radical C1C(0)0 is very unstable, and the exothermicity of reaction 87 would cause dissociation (equation 88) into C02 and atomic Cl. 

The Cl/OCl pathway. This process needs atomic chlorine to get started. The chlorine atoms react with ozone to produce CIO, which is in turn lost by reactions with atomic oxygen for a net loss of ozone ... 

Methane is the most abundant hydrocarbon in the atmosphere. It plays important roles in atmospheric chemistry and the radiative balance of the Earth. Stratospheric oxidation of CH4 provides a means of introducing water vapor above the tropopause. Methane reacts with atomic chlorine in the stratosphere, forming HCl, a reservoir species for chlorine. Some 90% of the CH4 entering the atmosphere is oxidized through reactions initiated by the OH radical. These reactions are discussed in more detail by Wofsy (1976) and Cicerone and Oremland (1988), and are important in controlling the oxidation state of the atmosphere. Methane absorbs infrared radiation in the troposphere, as do CO2 and H2O, and is an important greenhouse gas (Lacis et al., 1981 Ramanathan et al., 1985). 

The osmium carbyne complex 115 reacts with elemental sulfur, selenium, and tellurium to afford the complexes 135 in which the element atoms "bridge the metal-carbon triple bond [Eq. (123)] (56). Complex 115 also reacts with transition metal Lewis acids such as AgCl or Cul to give dinuclear compounds with bridging carbyne ligands. Reaction with elemental chlorine results in addition across the metal-carbon triple bond to generate the chlorocarbene osmium complex 136 [Eq. (124)]. 

We would like to suggest, that an attack of a chlorine takes place first at one of the silicon atoms of the tri- or tetrasilane under discussion to form a pentacoordinated silicon. In a second step, a silylene is generated which inserts into a silicon-chlorine bond of the disilane while the silicon skeleton of the oligosilane is shortened by one silicon atom. The source of the attacking chlorine is not yet known An intramolecular reaction with a chlorine of a chloromethylsilyl-sidechain and the central silicon might occur, or remaining traces of the aluminium trichloride, used for the chlorination, might induce the reaction. This is possible since only catalytic amounts would be necessary to cause the decomposition. 

The pseudo-first-order rate constant for the reaction of atomic chlorine with Br2 has been determined by means of measurements of the Cl resonance fluorescence. Yellowish-orange M Cl (M = Li, Na, K, Rb, Cs, or Ba) species have been produced in low-temperature matrixes. Resonance Raman spectra of... 

Tedder and co-workers [154] have examined the kinetics of the photoaddition of SFsCl to several olefins. SF5CI photolyses readily, and the kinetics suggest a moderately complex series of reactions with both chlorine atoms and SFj radicals being engaged in chain propagation, e.g. for ethylene... 

The atomic reactions of iodine or bromine are often speeded up by the introduction of small amounts of chlorine or fluorine into the reaction mass. As little as 0.015 mole of elemental fluorine will initiate the reaction of atomic chlorine with benzene to form hexachlorocyclohexane. 

Reaction with atomic oxygen produces another chlorine free radical ... 

E12.1 The decomposition of ozone with atomic chlorine follows a reaction mechanism in two steps. The direct reaction is difficult since the binding ruptures may occur only at high temperatures and need high energy demands. As observed, the reaction can occur with less energy, just because of the formation of intermediates. 

An interesting instmmental development has been described by Hanson et al. [184], who demonstrated the ability of PTR-MS to detect peroxy radicals. These radicals were produced in a laminar flow reactor via an initial reaction of atomic chlorine with an alkane to produce an alkyl radical, which was followed by reaction with O2 to generate the peroxy radical. The PTR-MS instrument was operated under extremely low E/Nconditions (18-34 Td), which ensured that H30+(H20) cluster ions (n > 0) dominated rather than bare H3O+ reagent ions, because alkanes do not react with protonated water clusters. The detection of methyl and ethyl peroxy radical species was found to be adversely affected by water vapour, whereas that for the cylcohexyl peroxy radical was found to be much less affected. A particularly powerful feature of this work was the ability to map the formation of product distributions in organic reaction systems involving peroxy radicals. 

Write a balanced chenfical equation for the substitution reaction in which one of the hydrogens on an end carbon of butane is replaced by a chlorine atom through reaction with elemental chlorine. Name the resulting compound. 

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