OCHEM 1 Final Reagents

Acids and Bases

Fundamental reagents that facilitate a variety of reactions including protonation, deprotonation, elimination, and substitution.

Strong Acids

HCl, HBr, HI, H₂SO₄: Used for acid-catalyzed reactions, protonation of alcohols, and hydrohalogenation of alkenes and alkynes.

Strong Bases

NaOH, KOH, NaOEt, NaOMe, KOC(CH₃)₃: Used for deprotonation, elimination (E2) reactions, and saponification.

Sodium Amide (NaNH₂)

A very strong base, often used to deprotonate terminal alkynes to form acetylide ions.

Lithium Diisopropylamide (LDA)

A strong, bulky base used for the irreversible formation of kinetic enolates from ketones.

Addition Reactions

Transformations involving double and triple bonds.

Hydrogenation

H₂ with metal catalyst (Pd, Pt, Ni): Reduction of alkenes/alkynes to alkanes via syn addition.

Halogenation

Br₂ or Cl₂: Anti addition of halogens to alkenes/alkynes.

Halohydrin Formation

Br₂ or Cl₂ in H₂O: Anti addition of -OH and halogen.

Anti-Markovnikov Hydrobromination

HBr, ROOR (peroxides): Via a free-radical mechanism.

Acid-Catalyzed Hydration

H₂O, H₂SO₄: Markovnikov addition of -OH.

Oxymercuration-Demercuration

1) Hg(OAc)₂, H₂O; 2) NaBH₄: Markovnikov addition of -OH.

Hydroboration-Oxidation

1) BH₃·THF; 2) H₂O₂, NaOH: Anti-Markovnikov addition of -OH, syn addition.

Syn-Dihydroxylation

1) OsO₄; 2) NaHSO₃/H₂O or NMO: Syn addition of two -OH groups.

Ozonolysis

1) O₃; 2) Zn, H₂O or DMS: Oxidative cleavage of alkenes to form aldehydes and ketones.

Simmons-Smith Reagent

CH₂I₂, Zn(Cu): Forms a cyclopropane ring from an alkene.

Oxidizing Agents

PCC or PDC: Mild oxidizing agents that convert primary alcohols to aldehydes and secondary alcohols to ketones.

Chromic Acid

CrO₃, Na₂Cr₂O₇, or H₂CrO₄: Strong oxidizing agents that convert primary alcohols to carboxylic acids.

Sodium Borohydride (NaBH₄)

A mild reducing agent used to reduce aldehydes and ketones to primary and secondary alcohols.

Lithium Aluminum Hydride (LiAlH₄)

A strong reducing agent that reduces aldehydes, ketones, esters, and carboxylic acids to primary alcohols.

Wolff-Kishner Reduction

H₂NNH₂, KOH, heat: Reduces carbonyls (ketones/aldehydes) to alkanes under basic conditions.

Clemmensen Reduction

Zn(Hg), conc. HCl: Reduces carbonyls to alkanes under acidic conditions.

PBr₃ and SOCl₂

Reagents for converting alcohols into alkyl bromides and chlorides, respectively.

Grignard Reagent (RMgX)

Strong nucleophiles and bases used to add alkyl groups to carbonyl compounds.

Finkelstein Reaction

NaI in acetone: Converts alkyl chlorides to alkyl iodides via SN2.

Sodium Azide (NaN₃)

A good nucleophile for SN2 reactions to introduce an azide group.

HCl, HBr, HI

Strong acids; protonate alcohols, initiate SN1/E1, add HX to alkenes (Markovnikov).

H₂SO₄ (conc.)

Strong acid; protonates OH, catalyzes dehydration of alcohols to alkenes (E1).

NaOH / KOH

Strong base; E2 eliminations and SN2 reactions.

NaOEt / NaOMe

Strong nucleophilic bases; SN2 or E2 depending on substrate.

t-BuOK (potassium tert-butoxide)

Strong bulky base; E2 giving Hofmann (less substituted) alkene.

NaNH₂ (sodium amide)

Very strong base; deprotonates terminal alkynes, forms acetylide ions.

LDA (lithium diisopropylamide)

Strong, bulky, non-nucleophilic base; deprotonates to form kinetic enolates.

H₂O / ROH (weak nucleophiles)

Promote SN1/E1 reactions with carbocation formation.

H₂ / Pd, Pt, or Ni

Hydrogenation of alkenes to alkanes (syn).

HBr, HCl, HI (no peroxides)

Markovnikov hydrohalogenation of alkenes.

HBr + ROOR (peroxides)

Anti-Markovnikov radical addition of HBr.

H₂O + H₂SO₄

Acid-catalyzed hydration (Markovnikov addition of OH).

1) Hg(OAc)₂, H₂O; 2) NaBH₄

Oxymercuration-demercuration: Markovnikov OH, no rearrangements.

1) BH₃·THF; 2) H₂O₂, NaOH

Hydroboration-oxidation: anti-Markovnikov, syn OH addition.

Br₂ / Cl₂

Anti addition of halogens.

Br₂ / H₂O

Halohydrin formation (anti addition of OH and halogen).

OsO₄; NMO or NaHSO₃/H₂O

Syn-dihydroxylation (adds two OH syn).

KMnO₄ (cold, dilute)

Syn-dihydroxylation.

1) O₃; 2) DMS or Zn/H₂O

Ozonolysis of alkenes to aldehydes/ketones.

CH₂I₂, Zn(Cu)

Simmons-Smith: cyclopropanation.

NBS (N-bromosuccinimide)

Radical allylic/benzylic bromination.

H₂ / Lindlar catalyst

Reduces alkynes to cis-alkenes (syn).

Na°, NH₃ (l)

Reduces alkynes to trans-alkenes (anti).

HX (1 equivalent)

Adds Markovnikov; forms vinyl halide.

Br₂ (1 equivalent)

Forms trans or cis dibromoalkene.

1) HgSO₄, H₂SO₄; H₂O

Markovnikov hydration of terminal alkynes → ketones.

1) BH₃; 2) H₂O₂, OH⁻

Anti-Markovnikov hydration → aldehydes.

1) O₃; 2) H₂O

Ozonolysis of alkynes → carboxylic acids (CO₂ for terminal).

H₂SO₄ + heat

Dehydration of alcohols → alkenes (E1).

POCl₃ + pyridine

E2 dehydration of alcohols (no rearrangements).

PBr₃

Converts alcohols to alkyl bromides (SN2, inversion).

SOCl₂

Converts alcohols to alkyl chlorides (SN2, inversion).

TsCl + pyridine

Converts OH to a tosylate (great leaving group).

TBDMS-Cl + imidazole

Protects alcohols as silyl ethers.

TBAF

Deprotects silyl ethers.

PCC / PDC

Oxidizes primary alcohols → aldehydes; secondary → ketones.

CrO₃, H₂CrO₄, Na₂Cr₂O₇ (Jones reagent)

Strong oxidation: primary alcohols → carboxylic acids; secondary → ketones.

KMnO₄ (hot, conc.)

Oxidative cleavage of alkenes; benzylic oxidation.

NaBH₄

Reduces aldehydes and ketones to alcohols.

LiAlH₄

Strong reduction: reduces aldehydes, ketones, esters, carboxylic acids.

DIBAL-H

Reduces esters to aldehydes.

Zn(Hg), HCl (Clemmensen reduction)

Reduces carbonyls to alkanes (acidic).

H₂NNH₂, KOH, heat (Wolff-Kishner)

Reduces carbonyls to alkanes (basic).

RMgX (Grignard reagents)

Adds R⁻ to carbonyls → alcohols; strong base.

RLi

Even stronger nucleophile/base; adds to carbonyls.

NaCN / HCN

Formation of cyanohydrins from carbonyls.

NH₃ or primary amines

Form imines (Schiff bases).

Secondary amines

Form enamines.

ROH, H⁺

Acetal formation (carbonyl protection).

NaI (in acetone)

Finkelstein reaction: alkyl chlorides → alkyl iodides (SN2).

NaN₃

SN2 introduction of azide.

CN⁻ (NaCN/KCN)

Strong SN2 nucleophile; adds CN group.

Br₂, FeBr₃

Electrophilic aromatic bromination.

Cl₂, FeCl₃

Electrophilic aromatic chlorination.

HNO₃, H₂SO₄

Nitration of benzene.

SO₃, H₂SO₄

Sulfonation.

R-Cl, AlCl₃

Friedel-Crafts alkylation.

RCOCl, AlCl₃

Friedel-Crafts acylation.

KMnO₄, heat

Benzylic oxidation → benzoic acid (requires benzylic H).

Base (e.g., NaOEt, NaOH)

Opens epoxides at less substituted carbon (SN2).

Acid (e.g., H₃O⁺)

Opens epoxides at more substituted carbon.