Historically-named benchmark chemical reactions: Haber-Bosch ammonia synthesis, methane combustion, Fischer esterification, Grignard addition, aldol condensation, saponification. Each instantiates the general machinery of stoichiometry,…
named-reactions
Haber-Bosch ammonia synthesis
Catalytic combination of N₂ and H₂ over iron (with K₂O/Al₂O₃ promoters) at ~400-500 °C and 150-300 bar to yield NH₃. Industrial-scale…
Methane combustion
Complete oxidation of methane to CO₂ + H₂O, releasing ~890 kJ/mol. Archetype of a hydrocarbon combustion reaction and the dominant…
Fischer esterification
Acid-catalysed condensation of a carboxylic acid with an alcohol to give an ester + water. Equilibrium process (Le Chatelier: drive toward…
Grignard reaction
Addition of an organomagnesium halide (RMgX) to a carbonyl to give an alcohol after protonation. Workhorse C-C-bond-forming reaction…
Aldol condensation
Base-catalysed enolate-addition of one carbonyl to another, followed by dehydration to give an α,β-unsaturated carbonyl. Central…
Saponification
Base-catalysed hydrolysis of an ester (typically a triglyceride) to give an alcohol (glycerol) and a carboxylate salt (soap).
Wittig reaction
Phosphorus ylide (R₃P=CHR') reacts with an aldehyde or ketone to give an alkene and triphenylphosphine oxide (Ph₃P=O). Proceeds via a…
Suzuki–Miyaura cross-coupling
Palladium-catalysed coupling of an aryl (or vinyl) halide with an aryl (or alkyl) boronic acid to form a new C–C bond in the presence of…
Olefin metathesis (Grubbs)
Ruthenium-alkylidene catalysts exchange the alkylidene halves of two olefins: R₁CH=CHR₂ + R₃CH=CHR₄ ⇌ R₁CH=CHR₃ + R₂CH=CHR₄ (and related…
Buchwald-Hartwig amination
Pd-catalyzed aryl halide + amine → aryl amine. Bulky phosphines (XPhos, RuPhos) enable room-T coupling of unactivated aryl chlorides +…
Mitsunobu reaction
Alcohol + nucleophile + DIAD/DEAD + PPh₃ → inverted stereochem coupling. Useful for SN2 on secondary alcohols, esterifications, ether…
Swern oxidation
Alcohol → aldehyde/ketone using (COCl)₂/DMSO/Et₃N at -78°C via alkoxysulfonium ylide. Mild, chemoselective; overcomes Cr-based…
Wacker process
PdCl₂/CuCl₂-catalyzed oxidation of ethylene to acetaldehyde (industrial, 1960s). Terminal alkenes → methyl ketones (Markovnikov).…
Mukaiyama aldol
Lewis-acid-catalyzed silyl enol ether + aldehyde. Chiral Lewis acids (Cu-box, Ti-BINOL) give asymmetric version. Alternative to lithium…
Diels–Alder [4+2] cycloaddition
s-cis diene + dienophile → cyclohexene; concerted, stereospecific; normal (EDG-diene + EWG-dienophile) vs inverse electron-demand.
Claisen rearrangement
[3,3]-sigmatropic of allyl vinyl ether to γ,δ-unsaturated carbonyl; chair-like TS; Ireland, Johnson, Carroll variants.
Cope rearrangement
[3,3]-sigmatropic of 1,5-hexadiene; degenerate unless substituents; bis-Cope in bullvalene; oxy-Cope acceleration.
Swern / Dess–Martin oxidations
DMSO/oxalyl chloride/Et₃N (Swern) and DMP (Dess-Martin) convert 1°/2° alcohols to aldehydes/ketones without over-oxidation.
Baeyer–Villiger oxidation
Ketone + peracid → ester; migratory aptitude H > tert > cyc > sec > benzyl > prim > Me; retention at migrating C.
Beckmann rearrangement
Oxime → amide with acid; anti group migrates; industrial caprolactam from cyclohexanone oxime.
Hofmann/Curtius/Schmidt/Lossen rearrangements
Nitrene intermediates give R-NCO → R-NH₂; C-C to C-N migration with retention; isocyanate then amine.
Friedel–Crafts acylation/alkylation
AlCl₃-mediated EAS; acylation avoids over-reaction; alkylation susceptible to carbocation rearrangement & polyalkylation.
Grignard reaction scope
RMgX + C=O, C=N, CO₂, RCN → product; Schlenk equilibrium; Reformatsky and Barbier variants.
Birch reduction
Li/Na in NH₃(l)/ROH reduces aromatics to 1,4-dihydro; EDG ortho/meta, EWG ipso/para product regioselectivity.
Robinson annulation
Michael addition + intramolecular aldol → cyclohexenone; classic steroid synthesis intermediate.
Chan–Lam amination
Cu-mediated N-arylation with arylboronic acids; amines, amides, azides as coupling partners; mild aerobic conditions.
Sonogashira coupling
Pd/Cu-cat aryl halide + terminal alkyne; gives aryl alkynes; extensively used in pharmaceuticals, optoelectronics.
Passerini & Ugi multicomponent reactions
Isocyanide + acid + aldehyde (Passerini) or +amine (Ugi) in one pot; high atom economy; peptide-like scaffolds.