Chlorination rearrangement during

Since the synthesis of VC A occurs via the following reaction, chlorine-containing substances may be formed as intermediates or byproducts or by rearrangement during the chlorination reaction, and they may be responsible for the inhibition periods. 

The combined mass of the sodium and chlorine that react (the reactants) exactly equals the mass of the sodium chloride that forms (the product). This law is consistent with the idea that matter is composed of small, indestructible particles. The particles rearrange during a chemical reaction, but the amount of matter is conserved because the particles themselves are indestructible (at least by chemical means). 

The vapor-phase chlorination reaction occurs at approximately 200-300°C. The dichlorobutene mixture is then treated with NaCN or HCN in presence of copper cyanide. The product 1,4-dicyano-2-butene is obtained in high yield because allylic rearrangement to the more thermodynamically stable isomer occurs during the cyanation reaction ... 

It was shown that no rearrangement of isobutyl radical to tert-butyl radical (which would involve the formation of a more stable radical by a hydrogen shift) took place during the chlorination of isobutane. 

A second way of synthesizing it is from 2 -carboxy-4-chlorobenzophenone (21.3.21), which during reduction with zinc in acetic acid transforms into 3-(4 -chlorophenyl)phthalide (21.3.27). Sulfonylchlorination of this gives the corresponding snl-fonylchloride (21.3.28), which upon reaction with phosphorous pentachloride is chlorinated into 3-(4 -chlorophenyl-3 -chlorosulfo)-3-chlorophtalide (21.3.25). This is reacted with aqueous ammonia in the aforementioned manner, and it rearranges into chlorothalidone (21.3.26) [50]. 

An interesting 1,3-chlorine shift reaction is reported to occur during the photochlorination of Ar-benzylperfluoroalkanimidoyl chlorides 39.27 Photochlorination of 39 gives a mixture of 40 and its isomer 41. which was interpreted as being caused by a 1,3-chlorotropic isomerization of 40 to 41. In the presence of triethylamine, the mixtures of 40 and 41 isomerize completely to 1,3-dichloride 42. which was explained as having resulted from an equilibrium between 40 and 41. via a reversible 1,3-chlorotropic shift, with 40 transformed completely by a base-catalyzed 1.3-prototropic rearrangement to isomer 42. 

The Kurata process [76] is a two-step process which uses thermoplastic resins as raw material and adds catalysts that consist of five metallic elements such as Ni, Cu, A1 and so on. The temperatures of the two phases are 200-250°C and 360-450°C, respectively. During the cracking reaction, the polymer molecules are rearranged. Equipment for HCl neutralizing is positioned at the end of the process, so there is no clear limitation on the content of PVC in feedstocks. HCl can be easily removed at a rate of 99.91%, even when the content of PVC is as high as 20%, and the concentration of chlorine in the products is lower than 100 ppm. An important difference between this process and the others is that its products are mainly composed of kerosene. 

Although the chemistry of short-lived electrophilic terminal pho hinidene tungsten con lexes [11, 12] has received increased attention during the recent years, partially because of the versatility of 2Ff-azaphosphirene complexes [13, 14], only a single example of a rearrangement yielding a / -Cl-substituted r) -phosphaalkene complex - via a 1,2-chlorine shift - has been reported so far [15]. 

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