Functional Groups

Alkane

Hydrocarbon, C-C single bonds, non-polar; lowest reactivity.

Alkene

C=C double bonds, can undergo addition reactions; π-bond present.

Alkyne

C≡C triple bond, linear geometry; terminal alkynes acidic.

Aldehyde

carbonyl group at end of chain (–CHO), electrophilic; reagents attack carbonyl C.

Ketone

carbonyl in the middle (–C=O–) electrophilic; less reactive than aldehydes.

Carboxylic Acid

–COOH, very acidic; forms H-bond dimers; parent of acid derivatives.

Ester

-COOR, smells/fragrances; formed from acid + alcohol.

Amide

–CONH₂ resonance stabilized; least reactive acid derivative.

Acid chloride

–COCl (shows up early as a reactive derivative) most reactive acid derivative; used for syn

Anhydride

CO–O–CO–

relative reactivity of acid derivative

Acid chloride > anhydride > ester ≈ acid > amide

Alcohol

-OH, hydrogen bonding; weakly acidic; good nucleophile.

Amines

–NH₂, –NHR, –NR₂ (primary, secondary, tertiary) basic; good nucleophile.

Thiols

-SH, nucleophilic sulfur; smell and oxidation tested.

Ether

C-O-C, fairly unreactive; weak H-bonding as acceptor.

Epoxide

three-membered ring with oxygen (often tested for ring opening) ring strain → reactive electrophile.

Alkyl halide

C–X (X = F, Cl, Br, I)

Used constantly in substitution/elimination (SN1/SN2/E1/E2)

Nitrile

–C≡N, polar; CN carbon is electrophilic.

Phenol

-OH directly attached to aromatic ring; much more acidic.

Carboxylate

Deprotonated carboxylic acid (–COO⁻); resonance stabilized base.

Acid Strength Trend

Carboxylic acid > phenol > alcohol ≈ water > amine

Nucleophile Strength

Amines > thiols > alcohols > water

SN2 Favored Substrate

Primary alkyl halides

SN1 Favored Substrate

Tertiary alkyl halides.