Chapter 16: Amines

Vocabulary flashcards covering key concepts from Chapter 16, Amines, including classification, nomenclature, properties, heterocyclic compounds, basicity, amine salts, and alkaloids.

Amines

Compounds that contain one or more organic groups bonded to a nitrogen atom.

Amines (general formulas)

Organic derivatives of ammonia that have the general formulas of RNH2, R2NH, or R3N.

Primary amine

An amine (RNH2) classified by one organic (alkyl) group bonded to the nitrogen atom.

Secondary amine

An amine (R2NH) classified by two organic (alkyl) groups bonded to the nitrogen atom.

Tertiary amine

An amine (R3N) classified by three organic (alkyl) groups bonded to the nitrogen atom.

Nitrogen (in amines)

Has five valence electrons, three of which form bonds and two (one lone pair) are unpaired.

Lone pair of valence electrons (in amines)

The unpaired electrons associated with the amine nitrogen, responsible for the chemistry of amines.

Quaternary ammonium ion (or cation)

Formed when a fourth organic group bonds to the nitrogen; has a permanent positive charge and forms ionic compounds.

Naming primary alkyl amines

Identify the alkyl group attached to nitrogen and add the ending suffix "-amine" to the primary alkyl group.

Naming non-heterocyclic secondary and tertiary amines

Add di- or tri- to the alkyl group name and the ending suffix "-amine".

N-substituted derivatives (for amines)

Naming convention for secondary or tertiary amines with different R groups; the parent compound contains the largest carbon chain and other groups are N-substituents.

Amino group

A common term for the -NH2 functional group; used as a prefix (amino-) when it is a substituent.

Aniline

The common name for the simplest aromatic amine.

Proteins

Polymers of alpha (α) amino acids with the general condensed structure H2N-CHR-COOH.

Amines (basicity)

The lone pair of electrons on the nitrogen produces a weak Brønsted-Lowry base or Lewis base.

Lewis base

A compound containing an unshared or lone pair of electrons.

Hydrogen bond (in amines)

An electrostatic force between a hydrogen atom covalently bonded to an electronegative donor atom (like N) and another electronegative acceptor atom (like O or N) with a lone-pair of electrons.

Amine boiling points (compared to alkanes and alcohols)

Higher than alkanes of similar size due to hydrogen bonding, but lower than alcohols of similar size because oxygen can form more hydrogen bonds per molecule than nitrogen.

Heterocycle

A ring that contains nitrogen or another atom in addition to carbon.

Heterocyclic nitrogen compounds

Nitrogen atoms associated in a ring with carbon atoms, which may be non-aromatic (e.g., piperidine) or aromatic (e.g., pyridine).

Amine cations

Formed (R3NH+) along with hydroxide anions (OH-) when aqueous solutions of amines, which are weakly basic, react with water.

Ammonium ion (from water)

A positive cation formed by the addition of a proton derived from water to an amine.

Ammonium ion (from hydronium)

A positive cation formed by the addition of a proton derived from a hydronium cation to an amine.

Naming alkylamine cations

Replace the ending "-amine" with "ammonium" (e.g., ethylamine becomes ethylammonium cation).

Ammonium cations (acidity)

Weakly acidic and react with bases, such as hydroxide anion, to regenerate the original amine.

Ammonium salt

An ionic compound composed of an ammonium cation and some sort of anion.

Ammonium salts (properties)

Generally odorless, white, crystalline solids that are more soluble than neutral amines.

Naming ammonium salts

Combine the 'cation and anion' names (e.g., ammonium chloride for NH4Cl).

Benzalkonium chlorides

Amine salts with antimicrobial and detergent properties, used in surgical scrubs and for sterile instrument storage.

Alkaloid

A naturally occurring, nitrogen-containing compound isolated from plants, usually basic, bitter, and poisonous.

Purpose of alkaloids in plants

Believed to protect plants from being eaten by animals due to their bitterness and poisonous nature.

Coniine

An alkaloid extracted from poison hemlock, used by Socrates to end his life.

Atropine

The toxic substance in deadly nightshade (belladonna); used in medications to reduce digestive tract cramping and as an antidote against nerve gases.

Solanine

An alkaloid found in potatoes and tomatoes, both belonging to the same botanical family as deadly nightshade.

Solanine increase in potatoes

Increased to dangerous levels when potatoes are exposed to sunlight or stored under very cold or very warm conditions; not destroyed by cooking but can be removed by peeling.

Morphine and Codeine

Alkaloids present in the poppy, used medicinally for pain.

Heroin

A substance synthesized from morphine; converts back into morphine in the body through the removal of two acetyl-groups.

Codeine

An alkaloid related to morphine, possessing two methoxy-groups instead of two acetyl-groups.