B bromination

Classify each of the following reactions as addition or substitution and write its chemical equation (a) chlorine reacts with methane when exposed to light (b) bromine reacts with ethene in the absence of light. 

Figure 3. Work function change for a) bromine on Ag 110 b) bromine and hydration water c) bromine and water to complete the inner layer d) bromine and multilayers of water.

Method B. Bromination TMA-Br3 (1.54 g, 10 mmol) and (PhC0)202 (0.24 g, 1 mmol) is added to the alkylarene (10 mmol) in PhH (20 ml) at room temperature and the mixture is stirred until the colour disappears and the evolution of HBr stops. H20 (20 ml) is added and the organic phase is separated, washed well with H20 and aqueous Na2CO, (sat. soln.), dried (Na2S04), and evaporated to yield the brominated product. 

Read from right to left. b Suffix B = bromine prefix C - cyelo. c Number of fluorine atoms. d Number of hydrogen atoms plus one. c Number of carbon atoms minus one (omit if 0). f That is, discrepancy with a carbon valency of four after allowance for bromine... 

NHS b)Bromination of the resulting di-phenylamine with bromide-bromate(% hr) ... 

Note According to Dalbert Tranchant(Ref 3), the above direct bromination of acardite I is not as convenient as their method, which consists essentially of a)saponification of acardite Ifextracted from propellant) by boiling with 3N NaOH soln for 2 hrs H2N-COr N(CtHs)2 + H2O / C,HS. NH.C.H, + C02 + NH, b)Bromination of the resulting di-phenylamine with bromide-bromate(% hr) ... 

In the absence of AlBr3, the kinetic product is the 1-bromide, 74. Further bromination, if it occurs, takes place at the most remote bridgehead positions available to give 75 and 76. When AlBr3 is present in the reaction mixture, characteristically decreased selectivity is observed (see also Section II.B). Bromination at the 4-position is able to compete effectively and 77 is obtained as one of the bromination products. 

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