SN1 reaction: Two-step substitution through a carbocation; favors tertiary substrates and polar protic solvents SN2 reaction: One-step substitution with backside attack and inversion; favors methyl and primary substrates E1 reaction: Two-step elimination through a carbocation E2 reaction: One-step elimination needing a strong base and anti-periplanar geometry Zaitsev's rule: Elimination gives the more substituted alkene as the major product Hofmann product: The less substituted alkene, favored by bulky bases Carbocation stability: Tertiary > secondary > primary > methyl Leaving group: A group that departs with a pair of electrons; good ones are weak bases Nucleophile: An electron-rich species that attacks an electrophile Electrophile: An electron-poor species that accepts electrons Polar protic solvent: Solvent with O-H or N-H bonds, like water or ethanol Polar aprotic solvent: Polar solvent without O-H, like acetone or DMSO Electrophilic addition: Alkene pi bond attacks an electrophile, adding across the double bond Hydrohalogenation: Adding HX across an alkene Hydration of alkenes: Adding water to form an alcohol Hydrogenation: Adding H2 across a double or triple bond using a metal catalyst Halogenation of alkenes: Adding X2 across a double bond to give anti addition Hydroboration-oxidation: Anti-Markovnikov syn addition of water to an alkene Oxymercuration-demercuration: Markovnikov hydration of alkenes without rearrangements Epoxidation: Converting an alkene to an epoxide with a peroxyacid Ozonolysis: Cleaving a double bond with ozone to give carbonyls Dihydroxylation: Adding two OH groups across a double bond Free radical halogenation: Substituting H on an alkane by a halogen through radical steps Radical chain mechanism: Initiation, propagation, termination Electrophilic aromatic substitution: Replacing a hydrogen on an aromatic ring with an electrophile Nitration: Adding NO2 to an aromatic ring using nitric and sulfuric acid Friedel-Crafts alkylation: Adding an alkyl group to an aromatic ring using AlCl3 Friedel-Crafts acylation: Adding an acyl group to an aromatic ring Ortho/para director: Group that directs incoming electrophiles to positions 2 and 4 Meta director: Group that directs incoming electrophiles to position 3 Activating group: Electron-donating group that speeds up aromatic substitution Deactivating group: Electron-withdrawing group that slows aromatic substitution Nucleophilic acyl substitution: Nucleophile replaces a leaving group on a carbonyl carbon Fischer esterification: Acid-catalyzed reaction of a carboxylic acid and alcohol to form an ester Saponification: Base hydrolysis of an ester to a carboxylate and alcohol Amide formation: Reaction of an acid derivative with an amine Grignard reaction: Organomagnesium reagent adds to carbonyl compounds to form alcohols Organolithium reagent: Strongly basic carbon nucleophile like Grignards Reduction with NaBH4: Mild reduction of aldehydes and ketones to alcohols Reduction with LiAlH4: Strong reduction of carbonyls, esters and acids to alcohols PCC oxidation: Oxidizes primary alcohols to aldehydes Jones oxidation: Strong oxidation of primary alcohols to carboxylic acids Swern oxidation: Mild oxidation of alcohols using DMSO Aldol reaction: An enolate adds to a carbonyl to form a beta-hydroxy carbonyl Aldol condensation: Aldol addition followed by loss of water Claisen condensation: Ester enolate attacks another ester to give a beta-keto ester Michael addition: Nucleophile adds to the beta carbon of an alpha-beta unsaturated carbonyl Wittig reaction: Converts aldehydes and ketones into alkenes Diels-Alder reaction: A diene and a dienophile form a six-membered ring Cycloaddition: Concerted reaction forming a ring Williamson ether synthesis: Alkoxide attacks alkyl halide to form an ether Gabriel synthesis: Preparing primary amines from alkyl halides using phthalimide Hofmann elimination: Converts quaternary ammonium to the less substituted alkene Diazonium salt: Intermediate from aryl amines used to introduce many groups on rings Sandmeyer reaction: Replacing a diazonium group with a halide or cyanide using copper salts Cannizzaro reaction: Aldehydes without alpha hydrogens react to give an alcohol and an acid Baeyer-Villiger oxidation: Converts ketones into esters using a peracid Hydrolysis: Breaking a bond with water Dehydration of alcohols: Acid-catalyzed loss of water to form alkenes Tautomerization: Interconversion of keto and enol forms Resonance stabilization: Delocalization of electrons lowers energy Hammond postulate: Transition states resemble the nearest-energy species Kinetic vs. thermodynamic control: Fastest-formed versus most stable product Inversion of configuration: Stereochemical result of an SN2 reaction Racemization: Formation of equal amounts of both enantiomers Syn addition: Both groups add to the same face of a double bond Anti addition: Groups add to opposite faces Stereospecific: Different stereoisomers give different stereoisomeric products Regioselective: One direction of bond making is favored over another Protecting group: A temporary group masking a reactive site Retrosynthesis: Planning a synthesis by working backward from the target Rearrangement (hydride shift): Carbocation moves hydrogen to become more stable Polymerization: Joining monomers into long chains Addition polymer: Polymer formed by adding monomers without losing atoms Condensation polymer: Polymer formed with loss of a small molecule such as water Beckmann rearrangement: Oxime converts to an amide under acid Pinacol rearrangement: Diol converts to a ketone under acid Fries rearrangement: Aryl ester converts to a hydroxy aryl ketone Clemmensen reduction: Reduces a ketone or aldehyde to an alkane using zinc and acid Wolff-Kishner reduction: Reduces a ketone or aldehyde to an alkane under basic conditions Birch reduction: Reduces aromatic rings to dienes Heck reaction: Palladium-catalyzed coupling of an alkene with an aryl or vinyl halide Suzuki coupling: Palladium-catalyzed coupling of organoboron and organohalide Click chemistry: Fast, reliable reactions that join molecules, like azide-alkyne cycloaddition Free flashcards from Peabody at peabody.kids/flashcards/tp-orgchem-reactions