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Halogenation is a chemical reaction that replaces a hydrogen atom with a halogen atom. More specific descriptions exist that specify the type of halogen: fluorination, chlorination, bromination, and iodination.

In a Markovnikov addition reaction, a halogen like bromine is reacted with an alkene which causes the π-bond to break forming an haloalkane. This makes the hydrocarbon more reactive and bromine as it turns out, is a good leaving group in further chemical reactions such as nucleophilic aliphatic substitution reactions and elimination reactions

Several types of halogenation exist, including:

Bromination

bromination reaction mechanism

The reaction mechanism for an alkene bromination can be described as follows. The bromine - bromine covalent bond attracts the attention of the π-bonding electrons, the π-bonds being electron dense and Bromine being very electronegative. This leads to a weakening and eventual break where heat, plays a crucial role in driving the break forward of the π-bond. Once the π-bond has been broken, its electrons are transfered to Br₂, causing the Br-Br bond to be severed when the bonding electrons are transfered to the other bromine. At this stage there is the positively charged intermediate and the loose bromine ion (Br^-). The bonding of Bromine is special in this intermediate, due it's relatively large size compared to carbon, the bromide ion is capable to latching onto both carbons which once formed the π-bond, making a three-membered ring. Coming from the opposite direction as the Br₂, the Br^- loosens one of the C-Br Bonds, leaving the final brominated product, a brominated alkane.

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-'''Halogenation''' is a [[chemical reaction]] that replaces a [[hydrogen]] atom with a [[halogen]] atom.  More specific words exist that specify which halogen: fluorination, chlorination, bromination, and iodination.
+'''Halogenation''' is a [[chemical reaction]] that replaces a [[hydrogen]] atom with a [[halogen]] atom.  More specific descriptions exist that specify the type of halogen: fluorination, chlorination, bromination, and iodination.
-In a [[Markovnikov]] [[additon reaction]] (see Bromination below), [[bromine]] is ''added'' to an [[alkene]], this causes the [[pi bond|π-bond]] to break forming an [[alkane]]. This makes the [[hydrocarbon]] more reactive, [[bromine]] as it turns out, is a good [[leaving group]] in further chemical reactions such as [[Substitution reaction|S<sub>n</sub>1]], [[Substitution reaction|S<sub>n</sub>2]], [[Elimination reaction|E1]] and [[Elimination reaction|E2]]
+In a [[Markovnikov's rule|Markovnikov addition]] reaction, a halogen like [[bromine]] is reacted with an [[alkene]] which causes the [[pi bond|π-bond]] to break forming an [[haloalkane]]. This makes the [[hydrocarbon]] more reactive and [[bromine]] as it turns out, is a good [[leaving group]] in further chemical reactions such as [[nucleophilic aliphatic substitution]] reactions and [[elimination reaction]]s
 Several types of halogenation exist, including:
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 ==Bromination==
+[[Image:Bromination.png|right|bromination reaction mechanism]]
+The [[reaction mechanism]] for an alkene bromination can be described as follows. The [[bromine]] - bromine [[covalent bond]] attracts the attention of the π-bonding [[electrons]], the π-bonds being [[electron]] dense and Bromine being very [[electronegativity|electronegative]]. This leads to a weakening and eventual break where heat, plays a crucial role in driving the break forward of the [[pi bond|π-bond]]. Once the [[pi bond|π-bond]] has been broken, its [[electrons]] are transfered to Br<sub>2</sub>, causing the Br-Br bond to be severed when the bonding [[electrons]] are transfered to the other [[bromine]]. At this stage there is the positively charged intermediate and the loose bromine ion (Br<sup>-</sup>). The bonding of [[Bromine]] is special in this intermediate, due it's relatively large size compared to [[carbon]], the bromide [[ion]] is capable to latching onto both carbons which once formed the [[pi bond|π-bond]], making a three-membered ring. Coming from the opposite direction as the Br<sub>2</sub>, the Br<sup>-</sup> loosens one of the C-Br Bonds, leaving the final brominated product, a brominated [[alkane]].
-     [[Image:Bromination.png]]
-The Br-Br bond attracts the attention of the π-bonding [[electrons]] (π-bonds being e<sup>-</sup> dense and Br being very electronegative), this leads to a weakening and eventual break (heat, plays a crucial role in driving the break forward) of the [[pi bond|π-bond]]. Once the [[pi bond|π-bond]] has been broken, it's [[electrons]] are transfered to Br<sub>2</sub>, causing the Br-Br bond to be severed when the bonding [[electrons]] are transfered to the other [[bromine]]. At this stage there is the positivly charged intermidiate and the loose bromine ion (Br<sup>-</sup>). [[Bromine]] is somewhat special, due it's realativly large size (compare to [[carbon]]), the bromide [[ion]] is capable to latching onto both carbons which once formed the [[pi bond|π-bond]], making a three-membered ring. Coming from the opposite direction as the Br<sub>2</sub>, the Br<sup>-</sup> loosens one of the C-Br Bonds, leaving the final brominated product, a brominated [[alkane]].<br>
 ==See also==