| ORGANIC CHEMISTRY I CHEM 2323 |
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| ORGANIC CHEMISTRY I CHEM 2323 |
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CHAPTER 8 - ALKENES II - REACTIONS
A reaction in which two molecules combine to yield a single molecule of product is called an addition reaction.
The double bond (pi bonds) serve as a source of electrons (base). The compounds which it reacts with are electron deficient (acid). These acidic reagents that are seeking a pair of electrons are called electrophilic reagents.
The typical reaction of an alkene is electrophilic addition.
Electrophilic addition mechanism
Free radicals also seek an electron, so we can also find alkenes undergoing free-radical addition.
1. Additions of Hydrogen (hydrogenation)
3. Addition of hydrogen halides
Markovnikov's Rule - in the addition of an acid (HX) to the carbon-carbon double bond of an alkene, the hydrogen (H) of the acid attaches itself to the carbon that already holds the greater number of hydrogens.
If both carbons in the carbon-carbon bond holds the same number of hydrogens, neither product will predominate and roughly equal qualities of the two isomers are actually obtained.
If peroxides are present in the system, anti-Markovnikov addition occurs. (The acid hydrogen goes to the carbon with the least number of hydrogens)
5. Addition of Water: hydration
9. Ozonolysis
