Lecture on Alkenes and Organic Reactions

These flashcards cover key concepts and definitions related to alkenes and various organic reaction mechanisms from the lecture notes.

Alkenes

Unsaturated hydrocarbons containing one or more double bonds.

Index of Hydrogen Deficiency (IHD)

Indicates the number of multiple bonds or rings in a compound, calculated as 2C + 2 + N - H - X.

Conjugation

A phenomenon in molecules with multiple unhybridized p orbitals contributing to stability, often seen in systems like benzene.

Electrophilic Addition

A reaction where an electrophile adds to a double bond, typically forming a carbocation intermediate.

Regioselectivity

When a reaction favors the formation of one isomer over another due to stability of intermediates.

Markovnikov’s Rule

In electrophilic addition, the more stable intermediate is preferred, usually resulting in more substituted products.

Carbocation Rearrangement

The process by which an unstable carbocation stabilizes itself through shifts or rearrangements.

Hammond Postulate

The transition state of a reaction resembles the species (reactant or product) to which it is closer in energy.

Halogenation

Addition reactions involving halogens, typically resulting in stereoselective products.

Hydroboration-Oxidation

A reaction that introduces a hydroxide group and hydrogen in a non-Markovnikov manner to an alkene.

Oxymercuration-Reduction

A method to hydrate alkenes using mercury(II) acetate without carbocation rearrangements.

Dihydroxylation

The syn addition of two hydroxyl groups to an alkene, often utilizing osmium tetroxide.

Ozonolysis

A reaction that cleaves double bonds to form carbonyl compounds (ketones or aldehydes).

Reduction/Hydrogenation

The conversion of an alkene to an alkane by adding hydrogen, typically yielding a syn addition.