ORGO FINAL EXAM REACTANTS

Br₂, FeBr₃

Adds Br to an aromatic ring by electrophilic aromatic substitution (bromination of benzene).

benzene

Indicates benzene is the aromatic ring being functionalized in electrophilic aromatic substitution reactions

CuCN

Replaces an aryl diazonium group (Ar–N₂⁺) with a nitrile (Ar–CN) in a Sandmeyer cyanation; needs an aryl diazonium salt.

Ac₂O, DMAP, pyridine

Acetylates alcohols or phenols to give acetate esters (ROAc); used as a protecting group for –OH.

acidic CH₃OH

With carbonyls, forms acetals or hemiacetals; with carboxylic acids, forms methyl esters under acid‑catalyzed conditions.

HNO₃, H₂SO₄

Nitration of benzene: introduces a nitro group (NO₂) onto an aromatic ring via electrophilic aromatic substitution.

H₂SO₄, H₂O, heat

Sulfonation of benzene: introduces a sulfonic acid group (SO₃H) onto an aromatic ring under hot, strongly acidic conditions.

1. Fe, HCl; 2. NaOH

Reduces aromatic nitro groups (Ar–NO₂) to aromatic amines (Ar–NH₂), then neutralizes the acid.

Pd(OAc)₂, PPh₃, Et₃N, methyl acrylate

Heck coupling: couples an aryl or vinyl halide with an alkene (methyl acrylate) to form a new C–C bond.

(HOCH₂)₂, TsOH, reflux (high heat)

Converts aldehydes or ketones to cyclic acetals (acetonides) as protecting groups for carbonyls under acid and heat.

i. LiAlH₄; ii. H₂O

Strong hydride reduction of many polar π bonds: converts aldehydes, ketones, esters, acids, and amides to alcohols (and nitriles to amines) after aqueous workup.

m‑CPBA

Epoxidizes alkenes: converts C=C double bonds to epoxides (three‑membered cyclic ethers).

NaNH₂, NH₃

Very strong base; deprotonates terminal alkynes to give acetylide anions and promotes E2 eliminations to form alkynes from dihalides.

NaNO₂, HCl

Diazotizes primary aromatic amines (Ar–NH₂) to aryl diazonium salts (Ar–N₂⁺Cl⁻) under cold acidic conditions.

NaOH, H₂O

Strong aqueous base; commonly used for ester saponification (ester → carboxylate + alcohol) and base‑mediated substitutions or eliminations.

i. NaOEt, EtOH; ii. Heat

Performs E2 elimination on suitable substrates (for example alkyl halides) to form the more substituted alkene (Zaitsev product) under hot basic conditions.

NaBH₄

Mild hydride reducing agent that converts aldehydes and ketones to alcohols, usually without reducing esters or acids.

TBSCl, Et₃N

Protects alcohols by forming TBS (tert‑butyldimethylsilyl) ethers; the base scavenges HCl produced.

i. Mg⁰, Et₂O; ii. acetone

Step 1: forms a Grignard reagent (R–MgX) from an alkyl or aryl halide; step 2: the Grignard adds to acetone to give a tertiary alcohol after workup.

n‑Bu₄N⁺F⁻ (TBAF)

Provides fluoride to remove silyl protecting groups such as TBS, regenerating the free alcohol from silyl ethers.

mCPBA

Converts an alkene into an epoxide (three‑membered C–O–C ring); needs a C=C double bond.

NaOCH₃ (on epoxide)

Strong base/nucleophile that opens an epoxide ring by nucleophilic attack, giving an alcohol with an –OCH₃ substituent.

NaOH then alkyl OTs

NaOH deprotonates an alcohol to RO⁻, which then does SN2 on a primary alkyl tosylate (ROTs) to extend the carbon chain and release NaOTs.

NaOCl, TEMPO (cat.)

Oxidizes a primary alcohol to an aldehyde (secondary to ketone) under mild, buffered conditions (pH ≈ 4–5).

N₂H₄ (hydrazine) with carbonyl

Adds across C=O to form a hydrazone (C=N–NH₂), setting up for Wolff–Kishner reduction.

KOt‑Bu, DMSO, heat (on hydrazone)

Strong base and heat drive Wolff–Kishner reduction: convert carbonyl carbon (via hydrazone) into CH₂, releasing N₂ gas (C=O → CH₂).

Ph₃P, then n‑BuLi with alkyl halide

Converts a primary alkyl halide into a phosphonium ylide (Wittig reagent, Ph₃P=CHR) by forming and deprotonating a phosphonium salt.

Wittig ylide + aldehyde

Performs Wittig reaction: replaces aldehyde C=O with C=C, joining the ylide carbon to the carbonyl carbon to form an alkene.

CH₃I (excess) with amine

Exhaustively alkylates an amine to give a quaternary ammonium iodide (NR₃ → NR₄⁺ I⁻).

Ag₂O, H₂O, heat (on quaternary ammonium iodide)

Forms quaternary ammonium hydroxide and induces Hofmann elimination to give the least substituted alkene plus a tertiary amine and AgI precipitate.

CH₃CH₂I with tertiary amine

Alkylates a tertiary amine to regenerate a quaternary ammonium salt (further Hofmann chemistry).

CH₃OH with anhydride

Alcoholysis of a carboxylic anhydride to give a methyl ester and a carboxylic acid.

SOCl₂ with carboxylic acid

Converts a carboxylic acid into an acid chloride, replacing –OH with –Cl.

CH₃CH₂OH with acid chloride

Nucleophilic acyl substitution: converts acid chloride into an ethyl ester, releasing HCl (usually trapped by base).

CH₃CH₂COCl, AlCl₃ (on benzene)

Friedel–Crafts acylation: installs a –COCH₂CH₃ acyl group onto an aromatic ring.

1 M HCl, H₂O (workup after acylation)

Acidic aqueous workup that removes AlCl₃ complex and protonates to give the free aryl ketone.

Zn(Hg), HCl(aq) (on aryl ketone)

Clemmensen reduction: reduces a carbonyl on an aromatic ring (Ar–CO–R) to CH₂ (Ar–CH₂–R) under strongly acidic conditions.

benzene, heat, AlCl₃; then H₂O with cyclic anhydride

Friedel–Crafts acylation of benzene using an anhydride, giving an aryl‑substituted dicarbonyl (succinyl phenyl) then hydrolysis to a carboxylic acid.

LiAlH₄ (on dicarbonyl acid/ester)

Strong hydride reducer that converts carboxylic acids and esters in the side chain to primary alcohols after aqueous workup.

Br₂, PPh₃ (on alcohol)

Appel‑type reaction: converts an alcohol into an alkyl bromide with inversion at carbon.

NH₃ (excess) with alkyl bromide

SN2 reaction that replaces Br with NH₂, forming a primary amine (plus NH₄Br).

PhCOCl, pyridine with amine

Acylates an amine to form an amide (benzamide), pyridine acting as base to neutralize HCl.

NH₃, HCN, H₂O with aldehyde

Strecker synthesis first step: aldehyde + NH₃ + HCN → α‑aminonitrile (adds –NH₂ and –CN to the carbonyl carbon).

H₃O⁺ (excess), heat with α‑aminonitrile

Hydrolyzes the nitrile to a carboxylic acid, giving an α‑amino acid from the aminonitrile.

i‑Pr₂NLi (LDA‑type base, –78 °C)

Strong, non‑nucleophilic base that forms a kinetic enolate at the most acidic α‑position of a carbonyl at low temperature for controlled C–C bond formation.

H₂O, heating (on β‑dicarbonyl from condensation)

Hydrolysis and decarboxylation of β‑keto esters/acids to give a simpler substituted carbonyl, releasing CO₂.

NaOCH₃ with β‑dicarbonyl ester

Deprotonates the central methylene of a β‑dicarbonyl ester to form an enolate for Claisen/malonate‑type C–C bond formation.

PhCH₂Br with β‑dicarbonyl enolate

SN2 alkylation: attaches a benzyl group (PhCH₂–) to the enolate carbon, forming a substituted β‑dicarbonyl.

H₃O⁺ (excess), heating with malonate/β‑keto diester

Hydrolyzes esters to acids and decarboxylates to give a substituted acetic acid or similar product plus CO₂

Br₂, FeBr₃

Adds Br to an aromatic ring by electrophilic aromatic substitution (bromination of benzene).

benzene

Indicates benzene is the aromatic ring being functionalized in electrophilic aromatic substitution reactions

CuCN

Replaces an aryl diazonium group (Ar–N₂⁺) with a nitrile (Ar–CN) in a Sandmeyer cyanation; needs an aryl diazonium salt.

Ac₂O, DMAP, pyridine

Acetylates alcohols or phenols to give acetate esters (ROAc); used as a protecting group for –OH.

acidic CH₃OH

With carbonyls, forms acetals or hemiacetals; with carboxylic acids, forms methyl esters under acid‑catalyzed conditions.

HNO₃, H₂SO₄

Nitration of benzene: introduces a nitro group (NO₂) onto an aromatic ring via electrophilic aromatic substitution.

H₂SO₄, H₂O, heat

Sulfonation of benzene: introduces a sulfonic acid group (SO₃H) onto an aromatic ring under hot, strongly acidic conditions.

1. Fe, HCl; 2. NaOH

Reduces aromatic nitro groups (Ar–NO₂) to aromatic amines (Ar–NH₂), then neutralizes the acid.

Pd(OAc)₂, PPh₃, Et₃N, methyl acrylate

Heck coupling: couples an aryl or vinyl halide with an alkene (methyl acrylate) to form a new C–C bond.

(
HOCH₂
)₂, TsOH, reflux (high heat)

Converts aldehydes or ketones to cyclic acetals (acetonides) as protecting groups for carbonyls under acid and heat.

i. LiAlH₄; ii. H₂O

Strong hydride reduction of many polar π bonds: converts aldehydes, ketones, esters, acids, and amides to alcohols (and nitriles to amines) after aqueous workup.

m‑CPBA

Epoxidizes alkenes: converts C=C double bonds to epoxides (three‑membered cyclic ethers).

NaNH₂, NH₃

Very strong base; deprotonates terminal alkynes to give acetylide anions and promotes E2 eliminations to form alkynes from dihalides.

NaNO₂, HCl

Diazotizes primary aromatic amines (Ar–NH₂) to aryl diazonium salts (Ar–N₂⁺Cl⁻) under cold acidic conditions.

NaOH, H₂O

Strong aqueous base; commonly used for ester saponification (ester → carboxylate + alcohol) and base‑mediated substitutions or eliminations.

i. NaOEt, EtOH; ii. Heat

Performs E2 elimination on suitable substrates (for example alkyl halides) to form the more substituted alkene (Zaitsev product) under hot basic conditions.

NaBH₄

Mild hydride reducing agent that converts aldehydes and ketones to alcohols, usually without reducing esters or acids.

TBSCl, Et₃N

Protects alcohols by forming TBS (tert‑butyldimethylsilyl) ethers; the base scavenges HCl produced.

i. Mg⁰, Et₂O; ii. acetone

Step 1: forms a Grignard reagent (R–MgX) from an alkyl or aryl halide; step 2: the Grignard adds to acetone to give a tertiary alcohol after workup.

n‑Bu₄N⁺F⁻ (TBAF)

Provides fluoride to remove silyl protecting groups such as TBS, regenerating the free alcohol