CHM 121: General Chemistry II - Amines

Comprehensive vocabulary flashcards covering the definition, classification, nomenclature, isomerism, preparation, and chemical properties of amines based on General Chemistry II lecture notes.

Amines

Derivatives of ammonia $NH_3$ that contain nitrogen attached to one or more alkyl (aliphatic amine) or aromatic groups (aromatic amine).

Amino group

The functional group designated as $-NH_2$.

Primary ($1^{\circ}$) Amine

An amine classified by having nitrogen bonded to only one carbon group.

Secondary ($2^{\circ}$) Amine

An amine where the nitrogen atom is bonded to two carbon groups.

Tertiary ($3^{\circ}$) Amine

An amine where the nitrogen atom is bonded to three carbon groups.

IUPAC Naming (Primary Amines)

The method of dropping the final "-e" of the parent alkane and replacing it with "-amine," using a number to locate the amino group on the parent chain.

Common Naming (Amines)

Naming alkyl groups in alphabetical order followed by the suffix "amine."

Amine Isomerism Types

Four types exhibited in amines: (a) chain isomerism, (b) positional isomerism, (c) metamerism, and (d) functional isomerism.

Ammonolysis of Alkyl Halides

A preparation method involving the reaction of an alkyl halide ($R-X$) with ammonia or amines, following an $S_N2$ mechanism where $R-X$ must be primary or methyl.

Reductive Amination

The synthesis of $2^{\circ}$ or $3^{\circ}$ amines from alkanals (aldehydes) or alkanones (ketones) using $H_2, Ni$ or $NaBH_3CN$ in the presence of a primary or secondary amine.

Hoffman Degradation

A reaction used to prepare primary amines by warming an acid amide ($RCONH_2$) with liquid bromine and a concentrated aqueous solution of an alkali.

Gabriel Synthesis

A multi-step method for preparing primary amines starting from Phthalimide and involving alkylation of the phthalimide ion followed by reaction with hydrazine ($NH_2NH_2$).

Amine Solubility

Amines are almost soluble in water because they can participate in hydrogen bonding.

Amine Boiling Points

The relative order is Hydrocarbons < Amines < Alcohols.

Basic Character of Amines

Amines behave as weak bases, reacting with water to form alkyl ammonium hydroxides: $R-NH_2 + H_2O \rightarrow R-NH_3^+ + OH^-$.

Blood pH

The approximately basic pH of our blood ($pH = 7.4$) is maintained in part by certain amines.

Relative Base Strength

The primary order of basicity for amines and ammonia is $RNH_2 > NH_3 > ArNH_2$, where aliphatic amines are stronger than ammonia, which is stronger than aromatic amines (anilines).

Acylation of Amines

The reaction of ammonia, primary, or secondary amines with acid chlorides, anhydrides, or esters to yield (substituted) amides.

Isocyanide (Carbylamine) Test

A qualitative test for primary amines where warming the sample with chloroform ($CHCl_3$) and alcoholic $KOH$ produces an isocyanide with a foul odor.

Reaction with Nitrous Acid ($HNO_2$)

Reaction where primary aliphatic amines yield unstable alkyldiazonium salts ($RN_2^+$), which immediately decompose into carbonium ions and nitrogen gas.

Azo Compounds

Highly colored, conjugated molecules formed by coupling reactions of diazonium salts, widely used in the dyestuff industry.