CHEM 219 - Handout: Most Common Functional Groups

Vocabulary practice flashcards covering the most common organic functional groups, including their definitions, formulas, and representative chemical structures from CHEM 219.

Primary Amine

a nitrogen atom is bonded to a single carbon group and two hydrogen atoms ($RNH_2$).

Secondary Amine

the nitrogen atom is bonded to two carbon groups and one hydrogen atom ($R_2NH$).

Tertiary Amine

nitrogen atom is bonded to three carbon groups with no directly attached hydrogen atoms ($R_3N$).

Primary Alcohol

hydroxyl group ($-OH$) attached to a carbon atom that is bonded to only one other carbon group ($RCH_2OH$).

Secondary Alcohol

hydroxyl group ($-OH$) attached to a carbon atom that is bonded to two other carbon groups ($R_2CHOH$).

Tertiary Alcohol

a hydroxyl group ($-OH$) attached to a carbon atom that is bonded to three other carbon groups ($R_3COH$).

Thiol (Thioalcohol)

g a sulfhydryl group ($-SH$) bonded to an alkyl or aryl carbon ($R-SH$).

Sulfide (Thioether)

in which a sulfur atom is bonded to two distinct carbon groups ($R-S-R'$).

Disulfide

A functional group characterized by a sulfur-sulfur single bond linking two organic groups ($R-S-S-R'$).

Sulfoxide

An organosulfur group containing a sulfinyl group ($S=O$) bonded to two carbon groups ($R-S(=O)-R'$).

Sulfone

An organosulfur group containing a sulfonyl group ($O=S=O$) bonded to two carbon groups ($R-S(=O)_2-R'$).

Sulfonic Acid

An acidic sulfur-containing functional group with the formula $R-SO_3H$ ($R-S(=O)_2OH$).

Primary Amide

A carboxylic acid derivative featuring a carbonyl group bonded directly to an unsubstituted amino group ($R-C(=O)NH_2$).

Secondary Amide

A carboxylic acid derivative featuring a carbonyl group bonded directly to a nitrogen bearing one organic group and one hydrogen ($R-C(=O)NHR'$).

Tertiary Amide

A carboxylic acid derivative featuring a carbonyl group bonded directly to a nitrogen bearing two organic groups and no hydrogens ($R-C(=O)NR'_2$).

Phenol

An aromatic functional group characterized by a hydroxyl group ($-OH$) bonded directly to a benzene ring ($Ar-OH$).

Ether

An organic compound consisting of an oxygen atom connected to two alkyl or aryl carbon groups ($R-O-R'$).

Thiophenol

An aromatic organosulfur compound characterized by a sulfhydryl group ($-SH$) attached directly to a benzene ring ($Ar-SH$).

Imine

A nitrogen analog of an aldehyde or ketone containing a carbon-nitrogen double bond ($R_2C=NR'$).

Iminium Salt

A positively charged species characterized by a protonated or alkylated carbon-nitrogen double bond ($[R_2C=NR'_2]^+$).

Enamine

An unsaturated compound characterized by an amino group attached directly to an alkene carbon-carbon double bond ($R_2C=CR-NR'_2$).

Amidine

A functional group characterized by a carbon atom bonded to both an imino group ($=NR$) and an amino group ($-NR_2$), having the general form $RC(=NR)NR'_2$.

Aldehyde

A carbonyl compound containing a carbonyl carbon bonded to at least one hydrogen atom and an alkyl or aryl group ($R-CH=O$).

Ketone

A carbonyl compound containing a carbonyl carbon bonded to two alkyl or aryl groups ($R-C(=O)-R'$).

Carboxylic Acid

A carbonyl compound consisting of a carbonyl group bonded directly to a hydroxyl group ($R-C(=O)OH$).

Peroxyacid (Peracid)

A carboxylic acid derivative that includes an extra peroxy oxygen atom, possessing the general structure $R-C(=O)OOH$.

Ester

A carboxylic acid derivative in which the acidic hydrogen is replaced by an alkyl or aryl carbon group ($R-C(=O)OR'$).

Thioester

A carboxylic acid derivative containing a carbonyl group bonded directly to an alkylthio or arylthio group ($R-C(=O)SR'$).

Carbamate (Urethane)

A carbonic acid derivative containing a carbonyl group bonded to both an amino nitrogen and an alkoxy/aryloxy oxygen ($R_2N-C(=O)-OR'$).

Urea

A carbonyl compound featuring a carbonyl group bonded directly to two amino nitrogen groups ($R_2N-C(=O)-NR_2$).

Imide

A functional group characterized by a nitrogen atom bonded to two acyl carbonyl groups ($R-C(=O)-NR'-C(=O)-R$).

Carbonate

A diester of carbonic acid containing a carbonyl group connected to two alkoxy or aryloxy oxygen atoms ($RO-C(=O)-OR'$).

Diacyl Peroxide

A compound containing two acyl groups bridged by an oxygen-oxygen single bond ($R-C(=O)-O-O-C(=O)-R$).

Diazonium

A functional group containing a terminal positively charged nitrogen-nitrogen triple bond attached to an organic group ($R-N^+\equiv N$).

Diazo

An organic functional group characterized by two linked nitrogen atoms bonded to a single carbon atom, exhibiting the resonance structure $R_2C=N^+=N^-$.

Azide

A functional group consisting of three contiguous nitrogen atoms linked together and attached to a carbon group ($R-N=N^+=N^-$).

Carboxylic Acid Anhydride

A carboxylic acid derivative formed from two acyl groups linked together via a single shared oxygen atom ($R-C(=O)-O-C(=O)-R$).

Acetal

A functional group in which a single carbon atom is bonded to two separate alkoxy groups, a hydrogen, and an alkyl group ($R-CH(OR')_2$).

Hemiacetal

A functional group in which a single carbon atom is bonded to both a hydroxyl group ($-OH$) and an alkoxy group ($-OR$).

Sulfonamide

An organosulfur group consisting of a sulfonyl group linked directly to an amine group ($R-S(=O)_2-NR'_2$).

Thioamide

An amide analog in which the carbonyl oxygen is replaced by a sulfur atom ($R-C(=S)-NR'_2$).

N,N'-Dialkyl Hydrazine

A substituted hydrazine derivative in which both nitrogen atoms bear an alkyl group and a hydrogen atom ($R-NH-NH-R'$).

Hydrazone

A compound containing a carbon-nitrogen double bond directly connected to an amino-type nitrogen ($R_2C=N-NR_2$).

Amine Oxide

A compound derived from a tertiary amine containing a coordinate covalent or polar bond between nitrogen and oxygen ($R_3N^+-O^-$).

Hydroxylamine

A functional group containing a nitrogen atom bonded directly to a hydroxyl group ($R_2N-OH$).

Ketene

An organic functional group containing a carbonyl carbon atom double-bonded to an adjacent carbon atom ($R_2C=C=O$).

Carboxylic Acid Halide (Acyl Halide)

A reactive carboxylic acid derivative in which the hydroxyl group has been replaced by a halogen atom ($R-C(=O)X$).

Alkyl Halide

An organic compound containing a halogen atom ($-F$, $-Cl$, $-Br$, or $-I$) bonded directly to an $sp^3$-hybridized carbon ($R-X$).

Nitrosamine (N-Nitrosoamine)

A functional group featuring a nitroso group ($-N=O$) bonded directly to an amine nitrogen atom ($R_2N-N=O$).

Oxirane (Epoxide)

A three-membered cyclic ether consisting of one oxygen atom and two carbon atoms.

Thiirane (Thioepoxide)

A three-membered saturated sulfur-containing heterocyclic ring consisting of one sulfur atom and two carbon atoms.

Aziridine

A three-membered saturated nitrogen-containing heterocyclic ring consisting of one nitrogen atom and two carbon atoms.

Oxime

A functional group containing a carbon-nitrogen double bond attached directly to a hydroxyl group ($R_2C=N-OH$).

Nitrile (Alkylcyanide)

An organic functional group characterized by a carbon-nitrogen triple bond ($R-C\equiv N$).

Isocyanide (Isonitrile)

A functional group containing a nitrogen-carbon triple bond in which the organic substituent is linked to the nitrogen ($R-N^+\equiv C^-$).

Isocyanate

A functional group containing the $-N=C=O$ group linked to an organic radical ($R-N=C=O$).

Thiocyanate

A functional group containing a sulfur atom bonded to a cyano carbon ($R-S-C\equiv N$).

Isothiocyanate

A functional group containing the $-N=C=S$ linkage bonded to an organic group ($R-N=C=S$).

Allene

A cumulene hydrocarbon functional group featuring two consecutive, adjacent carbon-carbon double bonds sharing a central $sp$-hybridized carbon ($R_2C=C=CR_2$).