Oxidation is a loss of electron density. There are two ways this can happen:
Bond formation between carbon and a more electronegative atom Bond-breaking between carbon and a less electronegative atom
Epoxidation (more electronegative atom)
An Epoxide is a cyclic ether with an oxygen atom in a three-membered ring.
The reactants are an alkene and a peroxy carboxylic acid. The common reagent used is meta-chloro-peroxybenzoic acid (MCPBA).
The double bond in the alkene reacts with the peroxycarboxcylic acid to form the cyclic ether called an epoxide. The by product of the react formed from the MCPBA reagent is a carboxylic acid.
The reagents used for the hydroxylation reaction are Osmium tetroxide OsO4 and pyridine. The Osmium tetroxide reacts with the double bond in the alkene to form a cyclic osmate intermediate. At this stage the double bond is now broken and two new carbon to oxygen bonds have formed. Sodium bisulphite in water is introduced to the reaction with adds hydrogen atoms to each oxygen bonded to the carbons, forcing the detachment of the osmium compound.
The product is a diol (two OH alcohol groups.
Alkene reacts with ozone to give a carbonyl compound.
A reaction with potassium permanganate can form carboxylic acids if hydrogens are present on the alkene group.