Organic Chemistry: Halogenoalkanes

These flashcards cover essential vocabulary and key concepts from the lecture on Halogenoalkanes in Organic Chemistry, focusing on their properties, reactions, and mechanisms.

Halogenoalkanes

Organic compounds containing at least one halogen atom covalently bonded to a carbon atom.

Nucleophile

An electron-rich species that can donate a pair of electrons.

S1 Reaction Mechanism

A reaction mechanism involving a single step with a carbocation intermediate.

S2 Reaction Mechanism

A reaction mechanism that involves a two-step process; involves a nucleophile attacking the electrophile.

Primary Halogenoalkane

A halogenoalkane where the halogen is attached to a carbon atom bonded to one other carbon.

Secondary Halogenoalkane

A halogenoalkane where the halogen is attached to a carbon atom bonded to two other carbons.

Tertiary Halogenoalkane

A halogenoalkane where the halogen is attached to a carbon atom bonded to three other carbons.

Hydroxide Ion (OH-)

A nucleophile that is important in the nucleophilic substitution reactions of halogenoalkanes.

Bond Enthalpy

The energy required to break a bond; crucial for understanding reactivity in halogenoalkanes.

Fluoroalkanes

Halogenoalkanes where the halogen is fluorine; least reactive due to strong C-F bonds.

Bromoalkanes

Halogenoalkanes where the halogen is bromine.

Chloroalkanes

Halogenoalkanes where the halogen is chlorine.

Iodoalkanes

Halogenoalkanes where the halogen is iodine; most reactive due to weak C-I bonds.

Alcohol Formation

A reaction where a halogenoalkane reacts with sodium hydroxide to produce an alcohol.

C-X Bond

The bond between carbon and a halogen atom, central to the reactivity of halogenoalkanes.

Silver Nitrate Reaction

A test to measure the rate of hydrolysis of halogenoalkanes by forming precipitates.

Precipitate

An insoluble solid formed when two solutions react.

Ethanol (C2H5OH)

A solvent often used in reactions with halogenoalkanes.

Nitrile Formation

The reaction of a halogenoalkane with cyanide ion (CN-) to produce a nitrile.

Primary Amine Formation

The reaction of halogenoalkanes with ammonia (NH3) to produce primary amines.

Alkene Formation

The reaction where halogenoalkanes are heated with sodium hydroxide to produce alkenes.

Reactivity Order

Iodoalkanes > Bromoalkanes > Chloroalkanes > Fluoroalkanes based on bond strength.

Hydrolysis Reaction

The reaction of halogenoalkanes with water or hydroxides to form alcohols.

Weak Nucleophile

A nucleophile that is less effective in forming a substitution product, such as water.

Electron-Rich Species

A species that is capable of donating electrons, essential in substitution reactions.

Skeletal Formula

A shorthand representation of molecular structure showing atoms and bonds.

Structural Formula

A representation of a molecule that shows how atoms are bonded in a compound.

Displayed Formula

A formula that shows how atoms are arranged and the bonds between them.

C-F Bond

The bond between carbon and fluorine; very strong and less reactive in substitution.

C-Cl Bond

The bond between carbon and chlorine; stronger than C-Br but weaker than C-F.

C-Br Bond

The bond between carbon and bromine; weaker than C-Cl and C-F.

C-I Bond

The bond between carbon and iodine; weakest carbon-halogen bond.

Ethanolic Ammonia

Ammonia dissolved in ethanol used in nucleophilic substitution reactions.

Amine Group (NH2)

Functional group derived from an amine, replacing a halogen in amination reactions.

Fastest Nucleophilic Reaction

Occurs with iodoalkanes due to the weakest C-I bond.

Slowest Nucleophilic Reaction

Occurs with chloroalkanes due to the strongest C-Cl bond.

Polar C-X Bond

A bond between carbon and halogen that has partial positive and negative charges.

Halogen Prefixes

Fluoro-, Chloro-, Bromo-, and Iodo- used in naming halogenoalkanes.

Organic Chemistry

The study of the structure, properties, composition, reactions, and synthesis of carbon-containing compounds.

Reactivitiy Trends

Trends in reactivity among halogenoalkanes based on bond strength and electronegativity.

Halogen Nomenclature

The method of naming halogenoalkanes based on their structure and halogen.

Bromopropane Example

1-bromopropane is an example where a bromine is attached to the first carbon of propane.

Alcohol Product

The result of the nucleophilic substitution of halogenoalkanes with hydroxide.

Nucleophilic Attack

The process through which a nucleophile attacks a carbon atom bearing a partial positive charge.

Bromoethane Reaction with KCN

Produces propanenitrile when reacted under reflux with potassium cyanide.

Hydrolysis Measurement Method

Using silver nitrate to measure how quickly precipitates form with different halogenoalkanes.

Nucleophile Examples

Hydroxide ion (OH-), cyanide (CN-), ammonia (NH3) are common nucleophiles.

Elimination Reaction

Occurs when halogenoalkanes lose a halogen and form an alkene.

Hydrolysis with Water

A slow alternative method of forming alcohols from halogenoalkanes.

Excess Ammonia in Reactions

Used to favor the formation of primary amines and prevent further substitutions.