Octet · Reactions

Every reaction, with the conditions that matter.

Browse reaction mechanisms, conditions, solvents, and selectivity notes.

83 records here
109 reference rows to cross-check

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83Reactions

63Reagents

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All 83 records · showing 60

ReactionCarbonyl

Acetal Formation

Remove water

Formula: ROH (excess), acid catalyst
SMILES: CC=O -> CC(OC)OC

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ReactionSubstitution

Acetoacetic Ester Synthesis

Makes substituted ketones (methyl ketones), Decarboxylation of β-keto acid, Can alkylate twice, Partner: malonic ester synthesis (makes acids)

Formula: NaOEt, R-X, then H₃O⁺/heat
SMILES: CCOC(=O)CC(=O)C -> CCC(=O)C

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ReactionCarbonyl

Acid-Catalyzed Ester Hydrolysis

Aqueous acid, reflux

Formula: H₂O, H₂SO₄ or HCl
SMILES: CC(=O)OCC -> CC(=O)O.CCO

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ReactionCarbonyl

Acyl Chloride Formation

SOCl₂ most common - gaseous byproducts escape, Acyl chlorides very reactive - use quickly, React with alcohols → esters, amines → amides

Formula: SOCl₂, or PCl₃, or PCl₅
SMILES: CC(=O)O -> CC(=O)Cl

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ReactionElimination

Alcohol Dehydration

Concentrated acid, heat

Formula: H₂SO₄, H₃PO₄
Detail: E1 / > 140°C
SMILES: CC(C)(C)O -> CC(C)=C

E1Zaitsev product (more substituted alkene)

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ReactionSubstitution

Alcohol to Alkyl Bromide (PBr₃)

OH is poor leaving group - PBr₃ activates it, Works for 1° and 2° alcohols, Alternative: SOCl₂ for chlorides

Formula: PBr₃
SMILES: CCO -> CCBr

Inversion (SN2 mechanism)

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ReactionSubstitution

Alcohol to Alkyl Chloride (SOCl₂)

Byproducts are gases - easy purification, Pyridine added to neutralize HCl, Works well for 1° and 2° alcohols

Formula: SOCl₂, pyridine (optional)
SMILES: CCO -> CCCl

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ReactionCarbonyl

Aldol Addition

Low temperature for addition (warm for condensation)

Formula: NaOH (dilute), LDA
SMILES: CC=O -> CC(O)CC=O

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ReactionCarbonyl

Aldol Condensation

Condensation = addition + elimination of water, Heat favors elimination (entropy), Product is α,β-unsaturated carbonyl

Formula: NaOH, heat
SMILES: CC=O -> CC=CC=O

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ReactionCarbonyl

Amide Formation from Acyl Chloride

Use 2 eq amine (one acts as base) or add Et₃N, Most stable carboxylic acid derivative, Peptide bonds are amide bonds

Formula: CH₃NH₂, excess amine or with base
SMILES: CC(=O)Cl -> CC(=O)NC

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ReactionAddition

Anti Dihydroxylation (Epoxide Opening)

Acid-catalyzed: opens at more substituted carbon, Base-catalyzed: opens at less substituted carbon

Formula: H₃O⁺/H₂O, or NaOH/H₂O
SMILES: CC1OC1C -> CC(O)C(O)C

Anti addition (OHs on opposite faces)

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ReactionAddition

Anti-Markovnikov HBr Addition (Radical)

Peroxide initiator (light or heat)

Formula: HBr, ROOR (peroxide)
SMILES: CC=C -> CCCBr

Anti-Markovnikov: Br on less substituted carbon

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ReactionSubstitution

Appel Reaction

ROH → RX conversion, CBr₄ for bromides, CCl₄ for chlorides, CI₄ for iodides, Mild conditions, Alternative to PBr₃, SOCl₂

Formula: CBr₄, PPh₃
SMILES: CCO -> CCBr

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ReactionOxidation

Baeyer-Villiger Oxidation

Ketone → Ester (oxygen inserted), Migratory aptitude: H > 3° > 2° ≈ aryl > 1° > methyl, Aldehydes give formate esters, Cyclic ketones → Lactones

Formula: mCPBA, CF₃CO₃H, peracetic acid
SMILES: CC(=O)c1ccccc1 -> CC(=O)Oc1ccccc1

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ReactionRearrangement

Beckmann Rearrangement

Acidic conditions, heat

Formula: H₂SO₄, PCl₅, SOCl₂
SMILES: CC(c1ccccc1)=NO -> CC(=O)Nc1ccccc1

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ReactionReduction

Birch Reduction

-33°C (liquid ammonia)

Formula: Na or Li, NH₃(l), ROH
SMILES: c1ccccc1 -> C1=CCC=CC1

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ReactionOxidation

Cannizzaro Reaction

Strong base, no α-hydrogens

Formula: NaOH (conc.), KOH
SMILES: c1ccccc1C=O -> c1ccccc1CO.c1ccccc1C(=O)[O-]

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ReactionAddition

Catalytic Hydrogenation

H₂ gas, metal catalyst

Formula: H₂, Pd/C or Pt or Ni
Detail: Reduction
SMILES: CC=CC -> CCCC

ReductionSyn addition

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ReactionCarbonyl

Claisen Condensation

Ester equivalent of aldol, Product is β-keto ester, Requires at least 2 α-hydrogens (for irreversible step)

Formula: NaOEt, EtOH
SMILES: CC(=O)OCC -> CC(=O)CC(=O)OCC

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ReactionPericyclic

Claisen Rearrangement

Thermal (150-200°C)

Formula: Heat
SMILES: C=CCOC=C -> C=CCC(=O)C

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ReactionReduction

Clemmensen Reduction (C=O → CH₂)

Heat

Formula: Zn(Hg), HCl (conc.)
SMILES: c1ccc(C(=O)C)cc1 -> c1ccc(CC)cc1

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ReactionPericyclic

Cope Rearrangement

Thermal (150-200°C)

Formula: Heat
SMILES: C=CCC=CC -> CC=CCC=C

Chair-like transition state preferred

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ReactionRearrangement

Curtius Rearrangement

Heat or UV light

Formula: Heat or photolysis
SMILES: CC(=O)N=[N+]=[N-] -> CN=C=O

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ReactionOxidation

Dess-Martin Oxidation

Very mild oxidation - many functional groups tolerated, Stops at aldehyde (no over-oxidation), Room temperature, neutral conditions, Expensive but selective

Formula: DMP (Dess-Martin periodinane)
Detail: CH₂Cl₂
SMILES: CCO -> CC=O

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ReactionReduction

DIBAL Reduction (Ester → Aldehyde)

-78°C, 1 equivalent

Formula: DIBAL-H (diisobutylaluminum hydride)
SMILES: CC(=O)OC -> CC=O

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ReactionPericyclic

Diels-Alder Reaction

Heat or pressure

Formula: Heat (or Lewis acid catalyst)
SMILES: C=CC=C.C=C -> C1CC=CCC1

Syn addition on both components. Endo product kinetically favored.

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ReactionAddition

Dissolving Metal Reduction (Alkyne → trans-Alkene)

-33°C (liquid ammonia)

Formula: Na or Li, NH₃ (liquid)
Detail: Reduction
SMILES: CC#CC -> C/C=C/C

ReductionAnti addition → trans-alkene

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ReactionElimination

E1 Elimination

Polar protic solvent, heat

Formula: Weak base or heat
Detail: E1 / Water or alcohol
SMILES: CC(C)(C)Br -> CC(C)=C

E1No stereospecificity (unlike E2)Zaitsev: more substituted alkene favored

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ReactionElimination

E2 Elimination

Strong base, heat

Formula: KOtBu, NaOEt, NaOH (conc.)
Detail: E2 / t-BuOH or EtOH
SMILES: CC(Br)CC -> CC=CC

E2Anti-periplanar geometry required. E/Z depends on which H is removed.Zaitsev: more substituted alkene favored (with most bases)

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ReactionCarbonyl

Enamine Formation

Remove water (Dean-Stark)

Formula: R₂NH (2° amine), acid catalyst
SMILES: CC(=O)CC -> CC(=CN(C)C)C

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ReactionAddition

Epoxidation (with mCPBA)

mCPBA = meta-chloroperoxybenzoic acid, Concerted mechanism, stereospecific, cis-alkene → cis-epoxide; trans-alkene → trans-epoxide

Formula: mCPBA, MMPP, peracetic acid
Detail: CH₂Cl₂
SMILES: CC=CC -> CC1OC1C

Syn addition (stereochemistry of alkene preserved)

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ReactionCarbonyl

Fischer Esterification

Reflux, remove water

Formula: MeOH, H₂SO₄ (cat.)
SMILES: CC(=O)O -> CC(=O)OC

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ReactionAromatic

Friedel-Crafts Acylation

Acylium ion resonance-stabilized → NO rearrangement, Product is deactivated → only monosubstitution, Better control than alkylation, Clemmensen/Wolff-Kishner removes C=O if needed

Formula: CH₃COCl, AlCl₃
Detail: Electrophilic Aromatic Substitution
SMILES: c1ccccc1 -> c1ccccc1C(=O)C

Electrophilic Aromatic Substitution

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ReactionAromatic

Friedel-Crafts Alkylation

Carbocation can rearrange!, Product more reactive than starting material → polyalkylation, Does NOT work on deactivated rings (nitrobenzene), AlCl₃ catalyst

Formula: (CH₃)₂CHCl, AlCl₃
Detail: Electrophilic Aromatic Substitution
SMILES: c1ccccc1 -> c1ccccc1C(C)C

Electrophilic Aromatic Substitution

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ReactionSubstitution

Gabriel Synthesis

Makes pure PRIMARY amines (no over-alkylation), Only works with 1° (and some 2°) halides (SN2), Alternative to direct alkylation of ammonia, Hydrazine releases amine, forms phthalhydrazide

Formula: R-X (1° alkyl halide), then N₂H₄ or NaOH/heat
SMILES: O=C1c2ccccc2C(=O)N1 -> CCN

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ReactionCarbonyl

Grignard Addition to Carbonyl

Anhydrous ether, then acid workup

Formula: CH₃MgBr, then H₃O⁺
SMILES: CC=O -> CC(C)O

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ReactionAddition

Halogenation of Alkene

Bromonium ion intermediate explains anti stereochemistry, In water: halohydrin forms instead, Test for unsaturation: Br₂/CCl₄ decolorizes, Mechanism shown for Br₂; Cl₂ works analogously via chloronium ion

Formula: Br₂ (or Cl₂)
Detail: Electrophilic Addition / CCl₄ or CH₂Cl₂
SMILES: CC=CC -> CC(Br)C(Br)C

Electrophilic AdditionAnti addition (trans-dihalide from cis-alkene)

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ReactionAromatic

Halogenation of Benzene

Lewis acid catalyst required for benzene, Phenol and aniline react without catalyst (activated), Halogens are ortho/para directors but deactivating

Formula: Br₂, FeBr₃ (or AlBr₃)
Detail: Electrophilic Aromatic Substitution
SMILES: c1ccccc1 -> c1ccccc1Br

Electrophilic Aromatic Substitution

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ReactionAddition

Halohydrin Formation

Water is nucleophile, not halide, Product can be converted to epoxide with base, Mechanism shown for Br₂; Cl₂ works analogously

Formula: Br₂/H₂O (or Cl₂/H₂O)
SMILES: CC=CC -> CC(O)C(Br)C

Anti additionOH on more substituted carbon (Markovnikov-like)

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ReactionCoupling

Heck Reaction

Aryl halide + Alkene → Substituted alkene, Generally gives trans (E) product, Nobel Prize 2010 (Heck), No organometallic partner needed (unlike Suzuki)

Formula: Alkene, Pd(OAc)₂, base (Et₃N), phosphine ligand
SMILES: c1ccccc1Br -> c1ccccc1/C=C/C

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ReactionSubstitution

Hell-Volhard-Zelinsky Reaction

α-Bromination of carboxylic acids, Goes through acid bromide intermediate, Br₂/P or Br₂/PBr₃, Product useful for further substitution

Formula: Br₂, PBr₃ or P
SMILES: CCC(=O)O -> CC(Br)C(=O)O

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ReactionAddition

Henry Reaction (Nitroaldol)

Like aldol but with nitroalkane, Product: β-nitro alcohol, Can dehydrate to nitroalkene, NO₂ can be converted to many groups (amine, carbonyl, etc.)

Formula: R-NO₂, base (NaOH, Et₃N)
SMILES: CC=O -> CC(O)C[N+](=O)[O-]

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ReactionElimination

Hofmann Elimination

Heat

Formula: Ag₂O/H₂O then heat, NaOH, heat
Detail: E2
SMILES: CC(C)C[N+](C)(C)C -> C=CC(C)C

E2Hofmann: less substituted alkene (opposite of Zaitsev)

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ReactionRearrangement

Hofmann Rearrangement

Aqueous base

Formula: Br₂, NaOH
SMILES: CC(=O)N -> CN

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ReactionAddition

Hydroboration-Oxidation

THF solvent, 0°C for BH₃, then oxidation

Formula: BH₃·THF, then H₂O₂/NaOH
Detail: Syn Addition
SMILES: CC=C -> CCCO

Syn AdditionSyn addition (H and OH end up on same face)Anti-Markovnikov: OH ends up on less substituted carbon

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ReactionAddition

Hydrohalogenation (HX Addition)

Carbocation stability determines regiochemistry, Rearrangements possible with carbocation intermediate, Follows Markovnikov's rule, Mechanism shown for HBr; HCl and HI work analogously

Formula: HBr (or HCl, HI)
Detail: Electrophilic Addition
SMILES: CC=C -> CC(C)Br

Electrophilic AdditionMarkovnikov: H adds to carbon with more H's, X to more substituted carbon

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ReactionOxidation

Jones Oxidation (Alcohol → Carboxylic Acid)

Strong oxidizing agent, 1° alcohol → carboxylic acid (through aldehyde), 2° alcohol → ketone, 3° alcohol → no reaction

Formula: CrO₃/H₂SO₄/acetone, Jones reagent
SMILES: CCO -> CC(=O)O

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ReactionOxidation

KMnO₄ Oxidative Cleavage

Heat, aqueous

Formula: KMnO₄ (hot, concentrated)
SMILES: CC=CC -> CC(=O)O.CC(=O)O

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ReactionReduction

LiAlH₄ Reduction

Very strong reducing agent, Reduces: aldehydes, ketones, esters, acids, amides, nitriles, Ester → 2 alcohols; Amide → amine, Violently reacts with water - use anhydrous!

Formula: LiAlH₄
Detail: Et₂O or THF (anhydrous!)
SMILES: CC(=O)OC -> CCO.CO

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ReactionAddition

Lindlar Reduction (Alkyne → cis-Alkene)

Lindlar catalyst is "poisoned" - stops at alkene, Lead (Pb) deactivates catalyst to prevent over-reduction, For trans-alkene, use dissolving metal reduction

Formula: H₂, Lindlar catalyst (Pd/CaCO₃/Pb)
Detail: Reduction
SMILES: CC#CC -> C/C=C\C

ReductionSyn addition → cis-alkene

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ReactionSubstitution

Malonic Ester Synthesis

Makes substituted acetic acids, Can alkylate twice for disubstituted, Decarboxylation: β-keto acid loses CO₂, Partner: acetoacetic ester synthesis (makes ketones)

Formula: NaOEt, R-X, then H₃O⁺/heat
SMILES: CCOC(=O)CC(=O)OCC -> CCC(=O)O

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ReactionAddition

Mannich Reaction

Three-component reaction: C-H acid + aldehyde + amine, Product is β-amino carbonyl (Mannich base), Important in alkaloid synthesis, Mannich base can undergo elimination to enone

Formula: HCHO, R₂NH (or NH₃), acid catalyst
SMILES: CC(=O)C -> CC(=O)CCN(C)C

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ReactionCarbonyl

Michael Addition

Conjugate (1,4) addition to α,β-unsaturated carbonyl, Soft nucleophiles prefer conjugate addition, Hard nucleophiles prefer 1,2-addition to C=O

Formula: Nucleophile (enolate, CN⁻, amine, thiol)
Detail: Conjugate Addition
SMILES: CC(=O)C=C -> CC(=O)CCC#N

Conjugate Addition

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ReactionSubstitution

Mitsunobu Reaction

Converts alcohol to other groups with INVERSION, Nucleophiles: azides, phthalimide, carboxylic acids, phenols, pKa of nucleophile must be < 15, Great for stereochemistry manipulation

Formula: DEAD or DIAD, PPh₃, Nucleophile (pKa < 15)
SMILES: CC(C)O -> CC(C)N3

Inversion of configuration (like SN2)

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ReactionReduction

NaBH₄ Reduction (Aldehyde/Ketone → Alcohol)

Mild reducing agent, Reduces: aldehydes, ketones, Does NOT reduce: esters, amides, carboxylic acids, alkenes, Chemoselectivity useful in synthesis

Formula: NaBH₄
Detail: MeOH or EtOH
SMILES: CC=O -> CCO

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ReactionCoupling

Negishi Coupling

Organozinc + Halide → Coupled product, More functional group tolerant than Grignard, Nobel Prize 2010 (Negishi), Works well for sp³-sp² coupling

Formula: R-ZnX (organozinc), Pd catalyst
SMILES: c1ccccc1Br -> c1ccccc1CC

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ReactionAromatic

Nitration of Benzene

Heat

Formula: HNO₃, H₂SO₄
Detail: Electrophilic Aromatic Substitution
SMILES: c1ccccc1 -> c1ccccc1[N+](=O)[O-]

Electrophilic Aromatic Substitution

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ReactionCoupling

Olefin Metathesis

Swaps alkene partners (2 RCH=CH₂ → RCH=CHR + CH₂=CH₂), Ring-closing metathesis (RCM) makes rings, Ring-opening metathesis polymerization (ROMP), Nobel Prize 2005 (Grubbs, Schrock, Chauvin), Mechanism: metal-carbene via metallacyclobutane (Chauvin mechanism)

Formula: Grubbs catalyst (Ru-based)
SMILES: C=CC -> CC=CC

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ReactionAddition

Oxymercuration-Demercuration

Markovnikov product without carbocation rearrangement, Mercurinium ion intermediate prevents rearrangement, Alternative to acid-catalyzed hydration

Formula: Hg(OAc)₂/H₂O, then NaBH₄
Detail: Electrophilic Addition
SMILES: CC=C -> CC(C)O

Electrophilic AdditionAnti additionMarkovnikov: OH on more substituted carbon

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ReactionOxidation

Ozonolysis

-78°C

Formula: O₃, then Zn/H₂O or DMS
SMILES: CC=CC -> CC=O.CC=O

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