Organic Chemistry Glossary
Glossary of Terms in Undergraduate Organic Chemistry & Their First Appearance Headings
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| Abbreviation, Term, Symbol, Unit | Class | Database Headings |
| Δ; ↑↓ | LAB | heat; reflux |
| (+) (dextrorotatory) | I | Stereochemistry |
| (-) (levorotatory) | I | Stereochemistry |
| 1,2-addition (direct addition) | I | Electrophilic Addition |
| [1,2]-hydride shift | I | Carbocations |
| [1,2]-alkyl shift | I | Carbocations |
| 1º, 2º, 3º, 4º | I | Classifying Carbons, C-Substituents |
| [1,3] migration | II | Pericyclic reactions |
| 1,4-addition (conjugate addition); Michael rxn | II | Michael addition |
| [1,5] migration | II | Sigmatropic Rearrangements |
| [1,7] migration | II | Sigmatropic Rearrangements |
| [2+2] cycloaddition | II | Pericyclic Reactions |
| [3+2] cycloaddition | II | Pericyclic Reactions |
| [4+2] cycloaddition | I | Pericyclic Reactions |
| 9-BBN | I | Electrophilic Addition |
| absolute (pure, neat) | LAB | |
| absolute configuration | I | Stereochemistry |
| absorbance spectrum | I | IR, UV-Vis Spectroscopy |
| acetal | II | Aldehydes and Ketones |
| Acetoacetic Ester synthesis | II | Named Reactions |
| acetylene | I | Alkynes |
| acetylide Anion | I | Alkynes |
| achiral | I | Stereochemistry |
| acid anhydride | II | Carboxylic Acid Derivatives |
| acid-catalyzed | I | Electrophilic Addition |
| acid halide (also Acyl halide) | II | Carboxylic Acid Derivatives |
| acid ionization constant (Ka) | I | Acids and Bases |
| activated charcoal (Norit); decolorizer | LAB | |
| activation energy | GEN | Kinetics vs. Thermodynamics |
| activating group (EDG) | II | Reactions of Benzene |
| actual yield (% yield) | LAB | |
| acyl group (also acetyl when = ‘Ac’) | II | Carboxylic Acid Derivatives |
| acylation reactions | II | Reactions of Benzene |
| acylium ion | II | Reactions of Benzene |
| Adenine (A) | II | Nucleic Acids |
| Adenosine | II | Nucleic Acids |
| addition reactions | I | Electrophilic Addition |
| adsorption | LAB | |
| Alanine (Ala or A) | II | Peptides and Proteins |
| alcohol (ROH) | I | Alcohols, Ethers, Epoxides |
| alcoholysis | II | Carboxylic Acid Derivatives |
| aldehyde | II | Ketones and Aldehydes |
| aldohexose | II | Sugars |
| Aldol reaction | II | Ketones and Aldehydes II |
| Aldol condensation | II | Ketones and Aldehydes II |
| aldose sugar | II | Sugars |
| alkali metal | GEN | |
| alkaline | GEN | Acids & Bases |
| Alkaline Earth Metals | GEN | The Periodic Table |
| alkaloid | II | Amines; Natural Products |
| alkane | I | Alkanes |
| alkene | I | Alkenes |
| alkyne | I | Alkynes |
| alkoxide (-OR) | I | Substitution |
| alkyl group/substituent | I | Nomenclature |
| alkyl halide (R-X) | I | Nomenclature |
| allene (1,2- or cumulated diene) | I | Dienes; Stereochemistry |
| allyl group/position | I | Resonance |
| allylic carbocations | I | Resonance |
| allylic position | I | Resonance |
| amino acid | II | Peptides and Proteins |
| α-anomer or epimer (internal acetal-axial bond) | II | Sugars |
| α-carbon (a carbon attached to functionality) | II | Functional groups |
| alpha-helix | II | Peptides and Proteins |
| anisotropy | I | NMR Spectroscopy |
| amalgam | II | Redox Reactions |
| ambident | II | Carbonyl Compounds |
| amide | II | Carboxylic Acid Derivatives |
| amine | I | Amines I & II |
| amine oxide (N-oxide) | I | Elimination |
| amu (Dalton) | GEN | |
| angle strain | I | Conformational Analysis |
| anhydrides, of acids | II | Carboxylic Acid Derivatives |
| anhydrous | LAB | |
| anion | GEN | |
| annealing | II | Nucleic Acids |
| anomer / anomeric | II | Sugars; Stereochemistry |
| anomeric carbon | II | Sugars |
| anomeric effect (negative hyperconjugation) | II | Electron Delocalization |
| anti conformation | I | Stereochemistry |
| anti addition | I | Electrophilic Addition |
| anti-Markovnikov Addition/regiochemistry | I | Regiochemistry |
| antiperiplanar | I | Conformational Isomerism |
| anti-aromaticity | II | Aromaticity |
| antibiotic | II | Drugs and Enzymes |
| anti-bonding molecular orbital | I | Molecular Orbital Theory |
| aprotic (solvent) | I | Solvents |
| aqueous | I | Solvents |
| arenium ion/intermediate | I | Aromatic Substitution |
| Arginine (Arg or R) | II | Amino Acids and Proteins |
| Arrhenius equation/constant/acid-base | I | Kinetics vs. Thermodynamics |
| aryl or Ar- (aromatic substituent) | I | Nomenclature |
| aryl halide (Ar-X) | II | Functional Groups |
| Asparigine (Asn or Q) | II | Amino Acids and Proteins |
| Aspartic Acid/Aspartate (Asp or E) | II | Amino Acids and Proteins |
| asymmetric (chiral) | I | Stereochemistry |
| asymmetric stretch/bend/wag | I | IR Spectroscopy |
| atomic mass | GEN | The Periodic Table |
| atomic number | GEN | The Periodic Table |
| atomic orbital (s, p, d, f) | GEN | Covalent Bonding |
| atomic radius | GEN | The Periodic Table |
| ATP (adenosine triphosphate) | II | Nucleic Acids |
| Avagadro’s Number (6.022 x 10-23) | GEN | Stoichiometry |
| axial | I | Conformational Analysis |
| azeotrope; azeotropic mixture | LAB | |
| azide anion | I | Substitution |
| aziridine | I | Amines; Heterocycles |
| Azimuthal Quantum Number | I | Electron Configuration |
| diazo coupling | II | Reactions of Benzene |
| backside attack | I | Nucleophilic Substitution |
| Baeyer-Villiger Oxidation | II | Aldehydes and Ketones |
| banana bonds (Walsh cyclopropane) | I | Cycloalkanes |
| base (Brønsted or Lewis) | I | Acids and Bases |
| base-catalyzed | I | Catalysis |
| base pairing | II | Nucleic Acids |
| Bond Dissociation Energy (BDE) | I | Covalent Bonds; Radicals |
| bending mode (IR) | I | IR Spectroscopy |
| benzylic carbocation | I | Carbocations |
| benzyl group (PhCH2-) | I | Nomenclature |
| benzylic position | I | Resonance |
| Benzyne | II | Reactions of Benzene |
| ß-anomer | II | Sugars |
| ß-carbon | I | Elimination, Conjugate addition |
| ß-elimination | I | Elimination |
| betaine | II | Aldehydes and Ketones |
| ß-pleated sheet | II | Peptides and Proteins |
| bicyclic (bridged or spiro-) | II | Nomenclature |
| bimolecular (2nd order) | I | Elimination, Substitution |
| biosynthesis | II | Synthetic Strategy |
| boat conformation | I | Conformational Analysis |
| boiling point (BP) | I | Alkanes |
| bond angle | I | Bonding & Hybridization |
| bond dipole | I | Bonding and Hybridization |
| bond length | I | Representing Organic Compounds |
| bond order | GEN | |
| bond rotation | I | Conformational Analysis |
| bond stretch | I | IR Spectroscopy |
| bond-line structure | I | Representing Organic Structures |
| Bonding Molecular Orbital (σ or π) | I | Molecular Orbital theory |
| borane | I | Electrophilic Addition |
| branching | I | Alkanes; Nomenclature |
| bridged | I | Polycyclic Compounds |
| bromination | I | Electrophilic Addition & Substitution |
| Brønsted Acid-Base Theory/Definition | I | Acids and Bases |
| butyl- | I | Nomenclature |
| Cahn-Ingold-Prelog (C-I-P) Rules | I | Nomenclature; Stereochemistry |
| carbanion | II | Carbanions; Reactive intermediates |
| carbocation or carbenium | I | Carbocations |
| carbohydrate (CH2O)n | II | Sugars |
| Carbon-13 NMR | I | NMR Spectroscopy |
| carbonyl (C=O) | II | Ketones and Aldehydes |
| carboxylate (-CO<2) | II | Carboxylic Acid Derivatives |
| carboxylic acid (-CO2H) | II | Carboxylic Acid Derivatives |
| carboxylic acid derivative | II | Carboxylic Acid Derivatives |
| canonical form (or mesomer) | I | Resonance |
| catalyst | I | Kinetics & Thermodynamics |
| catalytic hydrogenation | I | Redox Reactions; Addition |
| chain initiation (of radical reactions) | I | Radicals |
| chain propagation (of radical reactions) | I | Radicals |
| chain termination (of radical reactions) | I | Radicals |
| chair conformations | I | Conformational Analysis |
| chair flip (cyclohexane) | I | Conformational Analysis |
| chemical shift (δ) [ppm] | I | NMR Spectroscopy |
| chiral | I | Stereochemistry |
| chirality (or asymmetric) center | I | Stereochemistry |
| chlorination | I,II | Electrophilic Addition |
| cholesterol | II | Fats & Lipids |
| chromatography (several kinds) | LAB | Chemical Separation |
| cis– | I | Stereochemistry |
| Claisen condensation | II | Reactions at the α-carbon |
| Claisen rearrangement | II | Pericyclic Reactions |
| Clemmensen reduction | II | Redox Reactions |
| combustion | I | Alkanes |
| concerted (synchronous) reaction | I | Substitution |
| condensation reaction | II | Condensation Reactions |
| condensed formula (space-saving) | I | Representing Organic Compounds |
| configuration (absolute and relative) | I | Stereochemistry |
| configurational (stereo-) isomers | I | Stereochemistry |
| conformation | I | Isomerism |
| conformational isomers (conformers) | I | Isomerism |
| conformers | I | Isomerism |
| conjugate acid | I | Acids and Bases |
| conjugate base | I | Acids and Bases |
| conjugation | I | Resonance |
| constitutional (“structural”) isomers | I | Isomerism |
| coordination compounds | I | Organotransition Metal Chemistry |
| coupling | I | NMR Spectroscopy |
| coupling constant (J) [Hz] | I | NMR Spectroscopy |
| covalent bond | I | Atoms and Molecules |
| crown ethers (#C-cr-#O) | I | Alcohols, Ethers, Epoxides |
| cuprates | I,II | Organometallic Compounds |
| curved arrow formalism | I | Arrow pushing and Mechanism |
| cycloaddition reaction | I | Pericyclic Reactions |
| cycloalkane | I | Alkanes, Nomenclature |
| cyclobutadiene | II | Aromaticity |
| cyclooctatetraene | II | Aromaticity |
| cyclopentadienyl anion | II | Aromaticity |
| cyclopentadienyl cation | II | Aromaticity |
| cyclopropane | I | Cycloalkanes |
| cyclopropenyl cation | II | Aromaticity |
| Cysteine (Cys or C) | II | Peptides and Proteins |
| cystine bridge (Cys-Cys) | II | Peptides and Proteins |
| Cytosine (C) | II | Nucleic Acids |
| d- (same as (+)) | I | Stereochemistry |
| D- (dextrorotatory) | I | Stereochemistry |
| Dalton [Da] or [amu] | GEN | (an atomic mass unit) |
| deactivating group | II | Reactions of Benzene |
| deactivator | II | Reactions of Benzene |
| decarboxylation | II | Condensation Reactions |
| decomposition | LAB | |
| degenerate | I | Resonance Structures |
| delocalization | I | Resonance Structures |
| Deoxyribonucleic Acid | II | Nucleic Acids |
| deprotection / deblocking | II | Ketones and Aldehydes |
| deprotonate/deprotonation | I | Acids & Bases |
| DEPT | II | NMR spectroscopy |
| deshielded (downfield) | I | NMR spectroscopy |
| desolvation or dissolution | I | Solvents and Solutions |
| destructive interference | I | MO theory; NMR spectroscopy |
| detergent | II | Fats and Lipids |
| detonation | LAB | |
| deuterium (“heavy” hydrogen) 2H | I | Mass Spectrometry |
| Dewar benzene | I | Benzene & Aromatics |
| dextrorotatory (D or d or +) | I | Stereochemistry |
| dextrose (D-glucose) | I | Sugars |
| diastereomer | I | Stereochemistry |
| diatomic (A2) | GEN | |
| diaxial interaction | I | Conformational Analysis |
| diazonium ion | II | Reactions of Benzene |
| diazonium salt | II | Reactions of Benzene |
| diazotization | II | Reactions of Benzene |
| DIBAL or DIBAL-H | II | Redox Reactions |
| dichloromethane (methylene chloride) | LAB | Solvents (Chart) |
| dichromate | I | Redox Reactions |
| Dieckmann Condensation | II | Condensation Reactions |
| dielectric constant | I | Solvents |
| Diels-Alder Reaction; [4+2] cycloaddition | I | Dienes, Pericyclic Reactions |
| diene | I | Dienes, Conjugation |
| dieneophile | I | Dienes, Pericyclic Reactions |
| diethyl ether (Et2O | I | Ethers; Solvents |
| diffraction | I | Refractive Index |
| diffraction pattern | I | Refractive Index |
| dihedral angle | I | Conformational Analysis |
| dimer | I | Intermolecular forces |
| dimethylformamide (DMF) | I | Solvents |
| dimethyl sulfide (DMS) | I | Solvents |
| dimethyl sulfoxide (DMSO) | I | Solvents |
| diol | I | Redox Reactions |
| dipeptide | I | Peptides and Proteins |
| dipoles | I | Bonding and Hybridization |
| dipole moment | GEN | Covalent Bonds |
| disproportionation | II | Redox Reactions |
| diprotic acid | GEN | |
| diradical, triplet state | II | Alkenes, aromatization |
| directing group | I | Reactions of Benzene |
| disaccharide | II | Sugars |
| Dispersion Force (London Force) | I | Intermolecular Forces |
| distillation | LAB | |
| di-substituted | I | Nomenclature |
| disulfide -SS- | I | Peptides and Proteins |
| disulfide bridge -cys-S-S-cys- | I | Peptides and Proteins |
| divalent anions and cations | I | Formal Charge |
| double or (π) bond | I | Alkenes |
| Double Bond Equivalent (DBE) IU or IHD | I | Index of Unsaturation/IU/IHD |
| double-headed arrow (→) | I | Arrow Pushing and Mechanism |
| double helix | II | Nucleic Acids |
| doublet (d) | I | NMR Spectroscopy |
| downfield (de-shielded) | I | NMR Spectroscopy |
| drug | II | Drugs, Enzymes, and Activation |
| ε (electrical permittivity) | I | Solvents |
| E (Ger. entgegen) | I | Stereochemistry |
| E1 Mechanism | I | Elimination |
| E1 Reaction | I | Elimination |
| E1CB Mechanism | I | Elimination |
| E2 Mechanism | I | Elimination |
| E2 Reaction | I | Elimination |
| Ea | I | Kinetics & Thermodynamics |
| early (reactant-like) transition state | I | Kinetics & Thermodynamics |
| eclipsed | I | Conformational Analysis |
| % ee (enantiomeric excess) | I | Stereochemistry |
| election configuration | I | Electron Configuration |
| electron delocalization | I | Resonance; Conjugation |
| Electron Donating Group (EDG) | I | Dienes |
| electron pair repulsion | I | Structure and Bonding |
| electron-sea (‘sea-of-electrons’) | I | Special Topic |
| Electron Withdrawing Group (EWG) | I | Dienes |
| electronegative | GEN | Covalent Bonds |
| electronegativity | GEN | Covalent Bonds |
| electroneutral (non-polar) | GEN | Covalent Bonds |
| electrophile | I | Reactions |
| Electrophilic Addition Reaction | I | Alkenes |
| Electrophilic Aromatic Substitution | II | Reactions of Benzene |
| electropositive | GEN | Covalent Bonds |
| elimination reaction (e.g. | I | Eliminations |
| emulsion | II, LAB | Fats and Lipids |
| enamines | II | Ketones and Aldehydes; Amines |
| enantiomeric excess (% ee) | I | Stereochemistry |
| enantiomers | I | Stereochemistry, Chirality |
| endergonic (+ΔG) | I | Kinetics and Thermodynamics |
| endothermic (+ΔH) | I | Kinetics and Thermodynamics |
| energy profile or Reaction Coordinate Diagram | I | Kinetics and Thermodynamics |
| enols | I | Tautomerization |
| enolates | II | Reactivity at the α-Carbon |
| enolization | II | Reactivity at the α-Carbon |
| enone | II | Enones and Enoates |
| enthalpy (heat) of combustion | I | Kinetics and Thermodynamics |
| enthalpy of formation | I | Kinetics and Thermodynamics |
| enthalpy of hydrogenation | I | Kinetics and Thermodynamics |
| enzyme | II | Kinetics and Thermodynamics |
| epoxides | I | Alcohols, ethers, epoxides |
| equations of state | GEN | |
| equilibrium | GEN | |
| equilibrium constant (Keq) | GEN | |
| equatorial | I | Conformational analysis |
| equivalent (equimolar or stiochiometric) | I | Lab |
| ester | II | Carboxylic Acid Derivatives |
| Et- (ethyl) | I | Nomenclature |
| ether (R-O-R’) | I | Alcohols, Ethers, Epoxides |
| ethyl acetate (EtOAc) | I | Solvents |
| ethyl ether (Et2O) | I | Solvents |
| ethyne (acetylene or HCCH) | I | Alkynes |
| evaporation | GEN | Lab also Vaporization |
| excess of reagent (“xs“); a non-limiting qnty. | I | Lab |
| excited state (*) | I | Molecular Orbitals |
| exergonic (-ΔG) | I | Kinetics and Thermodynamics |
| exothermic (-ΔH) | I | Kinetics and Thermodynamics |
| expanded octet/shell | I | Trends in the Periodic Table |
| extinction coefficient (e) | I | Spectroscopy |
| fatty acid | II | Fats and Lipids |
| fingerprint region | I | IR Spectroscopy |
| first-order coupling | I | NMR Spectroscopy |
| first order splitting | I | NMR Spectroscopy |
| Fischer esterification | II | Carboxylic Acid Derivatives |
| Fischer Projection | I,II | Representing Compounds; Stereochemistry |
| Five Zone Analysis | II | Drug Formulation Medicinal Chem. |
| fluorination | II | Reactions of Benzene |
| formal charge | I | Bonding and Hybridization |
| fractional distillation | LAB | |
| fragment Ion (formerly “daughter” ion) | I | Mass Spectrometry |
| fragmentation reaction | I | Mass Spectrometry |
| free radical | I | Radicals |
| Friedel-Crafts acylation | II | Reactions of Benzene |
| Friedel-Crafts alkylation | II | Reactions of Benzene |
| front-side attack | II | |
| fullerenes | II | Allotropes of Carbon |
| functional groups | I | Functional Groups |
| fused | II | Polycyclic Ring Systems |
| Gas Chromatography (GC) | LAB | |
| gauche | I | Conformational Analysis |
| GC | LAB | |
| GC-MS | LAB | |
| geminal or (1,1) | I | Nomenclature |
| ‘geometric’ isomers (obsolete referring to E/Z) | I | Isomerism, Nomenclature |
| Gibbs Free Energy (G) | I | Kinetics and Thermodynamics |
| Gibbs-Helmholtz equation | I | Kinetics and Thermodynamics |
| Gilman reagent (R)2CuLi (lithium dialkyl cuprate) | I | Organometallics; Cuprates |
| glucose | II | Sugars |
| glutamic acid (Glu or E) | II | Peptides and Proteins |
| glutamine | II | Peptides and Proteins |
| glycerol (1,2,3-propanetriol) | II | Fats and Lipids |
| Glycine (Gly or G) | II | Peptides and Proteins |
| glycosidic bond/linkage | II | Sugars |
| Grignard Reaction | II | Carbonyl Compounds |
| Grignard Reagent, R-MgX | I | Organometallics |
| Grob Fragmentation | II | Named Reactions |
| ground state (GS) | I | Reaction Coordinate Diagrams |
| Guanine (G) | II | Nucleic Acids |
| 1,2-hydride [1,2-H] shift | I | Carbocations |
| 1H-NMR | I | NMR Spectroscopy |
| hv (Plank’s constant⋅wavelength) | GEN | Energy of a photon |
| H-Bond (hydrogen bond) | I | Intermolecular interactions |
| halide (Group VIIA substituent) | I | Functional Groups |
| haloalkanes (alkyl halides. R-X) | I | Functional Groups |
| haloarene (aryl halide, Ar-X) | I | Functional Groups |
| halogen | I | Trends in the Periodic Table |
| halogenation | I,II | Addition, Substitution |
| Hammond Postulate | I | Transition State Theory; RCD |
| Hard/Soft-Acid/Base (HSAB) Theory | I | Polar Reactions |
| Haworth projection (“hay-worth”) | II | Sugars |
| heat (enthalpy) of combustion | I | Kinetics and Thermodynamics |
| heat (enthalpy) of formation, Hf | I | Kinetics and Thermodynamics |
| heats of hydrogenation | I | Kinetics and Thermodynamics |
| hemiacetal (or hemiketal) | II | Ketones and Aldehydes |
| Henderson-HasselBalch equation | GEN | Acids and Bases |
| Henry’s Law | GEN | Partial Pressures |
| Hess’s Law | GEN | Heat summation |
| HETCOR | LAB | Advanced Spectroscopy |
| heteroatom | I | Functional Groups |
| heterocycle | I | Functional Groups |
| heterogeneous | I | Catalysis |
| heterolysis | I | Covalent Bonding |
| heterolytic bond cleavage | I | Transition State Theory |
| Highest Occupied Molecular Orbital (HOMO) | I | Molecular Orbitals |
| Histidine (His or H) | II | Amino Acids and Proteins |
| HMQC | II | NMR (Advanced) |
| HOAc = AcOH = acetic acid | I | Nomenclature |
| Hofmann degradation | II | Named Reactions |
| Hofmann elimination (anti-Zaitzev) | II | Named Reactions |
| Hofmann’s Rule (anti-Zaitzev) | I | Elimination |
| HOMO-LUMO Gap/energy | I | Molecular Orbitals |
| homogeneous | I | catalysis |
| homolysis | I | Covalent Bonds; Transition States |
| homolytic bond cleavage (homolysis) | I | Transition States |
| Hooke’s Law | GEN | |
| Hückel’s Rule (4n+2) | II | Aromaticity |
| hybridization (of orbitals) | I | Bonding and Hybridization |
| hydration | I | Electrophilic Addition |
| hydride (H:– anion) | I | Redox Reactions |
| hydroboration | I | Electrophilic Addition |
| hydroboration-oxidation | I | Electrophilic Addition |
| hydrolysis | II | Carboxylic Acid Derivatives |
| hydronium ion, H3O+ | I | Acids and Bases |
| hydrophilic | GEN | Solvents |
| hydrophobic | GEN | Solvents |
| hydrophobic Effect | GEN | Solvents |
| hygroscopic | LAB | |
| hyperconjugation | I | Electron Delocalization |
| I or spin quantum number (±½) | I | Electron Configuration |
| imidazole (imid.) | II | Aromatics; Heterocycles |
| imine | II | Aldehydes and Ketones |
| immiscible | I | Solvent and Solutions |
| in silico | GEN | (in glass) |
| in situ | I | (during the reaction) |
| in vitro | I | (in a model system) |
| in vivo | I | (in a living system) |
| indole | II | Aromatics; Alkaloids; Heterocycles |
| inductive effects | I | Electron Delocalization |
| Infrared spectroscopy | I | IR Spectroscopy |
| infrared spectrum | I | IR Spectroscopy |
| inhibitor | II | Radical Reactions |
| initiation | I | Radical Reactions |
| initiator | I | Radical Reactions |
| integration | I | NMR Spectroscopy |
| intermediate | I | Reactive Intermediates |
| intermolecular | I | Reaction Dynamics |
| internal alkene | I | Alkenes |
| internal alkyne | I | Alkynes |
| intramolecular | I | Reaction Dynamics |
| inversion of stereochemistry/configuration | I | Stereochemistry |
| iodination | I | Electrophilic Addition & Substitution |
| Iodoform reaction | II | Ketones and Aldehydes |
| ion | GEN | |
| ionic bond | GEN | Bonding and Hybridization |
| ionization | I | Bonding and Hybridization |
| i-Pr (isopropyl) | I | Nomenclature |
| ipso substitution | II | (Nucleophilic) Aromatic Substitution |
| IR (infrared) | I | IR Spectroscopy |
| isoelectronic | I | Organometallic Chemistry |
| isoleucine (Ile or I) | I | Amino Acids and Proteins |
| isomer | I | Isomerism |
| isomerization | I | Isomerism |
| isotope | I | Mass Spectrometry |
| IUPAC (Int’l Union of Pure & Applied Chemistry) | I | Nomenclature |
| Jahn-Teller Effect | I | Advanced Organic |
| Joule (J) or kilojoule (kJ) | GEN | |
| Jones Reagent (acidic dichromate) | II | Redox Reactions |
| Ka (acid dissociation constant) | I | Acids and Bases |
| kcal / kilocalorie or Calorie (C = 1000cal) | I | Equilibrium |
| kJ / kilojoule | I | Equilibrium |
| Kekulé structure | I | Representing Organic Compounds |
| Keq (equilibrium constant) | GEN | Equilibrium |
| keto isomer form | I | Tautomerism/Tautomerization |
| ketone | II | Ketones and Aldehydes |
| ketose | II | Sugars |
| ketoxime | II | Sugars |
| Kinetic Control/Product | I | Kinetics & Thermodynamics |
| l- (prefix) | I | Stereochemistry |
| L- (prefix) | I | Stereochemistry |
| lactam | II | Carboxylic Acid Derivatives |
| lactone | II | Carboxylic Acid Derivatives |
| late transition state | I | The Transition State |
| LDA (lithium diisopropylamide) | II | Ketones and aldehydes |
| Le Chateliér’s Principle | GEN | |
| leaving group | I | Substitution; Elimination |
| Leucine (Leu or L) | II | Peptides and Proteins |
| levorotatory (L or l or -) | I | Stereochemistry |
| Lewis acids & bases; definition | I | Acids and Bases |
| Lewis dot structure | I | Bonding and Hybridization |
| Lewis structure | I | Bonding and Hybridization |
| ligand | I | Hybridization; Organometallics |
| limiting reagent | LAB | |
| lipid | II | Fats and Lipids |
| lipophilic (aliphatic) | II | Fats and Lipids |
| lipophobic (hydrophilic) | II | Fats and Lipids |
| London (dispersion) forces | I | Intermolecular Forces |
| lone pair (electrons) | I | Bonding and Hybridization |
| long-range coupling | I | NMR Spectroscopy |
| Lowest Unoccupied Molecular Orbital (LUMO) | I | Molecular Orbital Theory |
| Lysine (Lys or K) | II | Amino Acids and Proteins |
| µ (mu) | I | Dipole Moment |
| M+ (molecular ion) | I | Mass Spectrometry |
| M+1 | I | Mass Spectrometry |
| M+2 | I | Mass Spectrometry |
| m/z (units of Mass Spectrometry) | I | Mass Spectrometry |
| main group elements (A group) | I | Trends in the Periodic Table |
| major groove | II | Nucleic Acids |
| Markovnikov Regiochemistry | I | Electrophilic Addition |
| Markovnikov’s Rule | I | Electrophilic Addition |
| mass spectrum | I | Mass Spectrometry |
| mass spectrometry | I | Mass Spectrometry |
| McLafferty Rearrangement | I | Mass Spectrometry |
| mCPBA | I | Redox Reactions |
| Me- (methyl) | I | Nomenclature |
| mechanism (re reactions) | I | Arrow Pushing and Mechanism |
| medicinal chemistry | II | Medicinal Chemistry |
| melting point (MP) | LAB | |
| mercaptan (thiol) | I | Sulfur Compounds |
| meso compound/diastereomer | I | Stereochemistry |
| mesomerism (see resonance) | I | Stereochemistry |
| mesylate (-OMs) | I | Substitution |
| meta- (1,3-) | I | Reactions of Benzene |
| meta director/directing | II | Reactions of Benzene |
| metals and metalloids | I | The Periodic Table |
| metabolism | II | Biochemistry |
| methanesulfonate | I | Substitution |
| methanesulfonic acid | I | Substitution |
| methine proton R3C-H | I | NMR Spectroscopy |
| Methionine (Met or M) | II | Peptides and Proteins |
| methylene group R2CH2 | I | NMR Spectroscopy |
| microscopic reversibility, principle of | I | Rxn Coord Diagrams |
| mineral acid | I | Acids and Bases |
| minor groove | II | Nucleic Acids |
| miscible | I | Solutions & Solvents |
| moiety | I | Functional Groups |
| mol | Gen | mole |
| molar mass / molecular weight | Gen | |
| mole (Avagadro’s Number of species) | Gen | |
| molecular formula (CnHm….) | Gen | Alkanes |
| molecular ion (M+); formerly “mother” ion | I | Mass Spectrometry |
| molecular model kit | I | Blog; Adjusting to organic chemistry |
| molecular sieve (MS) (3Å-4Å) | LAB | |
| molecular weight (MW or M) or molar mass | GEN | |
| molozonide | I | Redox reactions; Alkenes |
| molecular orbital (MO) | I | Molecular Orbitals |
| monosubstituted | I | Alkenes |
| multiplet (m) | I | NMR Spectroscopy |
| mutarotation | II | Sugars; Epimerization |
| N-bromosuccinimide (NBS) | I | Electrophilic Addition, Radicals |
| N-chlorosuccinimide (NCS) | I | Electrophilic Addition |
| N-iodosuccinimide (NIS) | I | Electrophilic Addition, Radicals |
| n- (normal or unbranched) | I | Nomenclature |
| n-BuLi | I | Alkanes; Organometallics |
| n+1 rule | I | NMR Spectroscopy |
| 4n rule | II | Aromaticity |
| 4n+2 (Hückel’s rule) | II | Aromaticity |
| NaBH4 | I | Redox Reactions |
| NaH | I | Substitution; Alcohols |
| Named Reaction | I | Named Reactions |
| Natural Product (Organic I, Intro to Synthesis) | II | Organic Subdivisions; Synthesis |
| Newman Projection | I | Conformational Analysis |
| nitration (-NO2) | II | Reactions of Benzene |
| nitrile | II | Carboxylic Acid Derivatives |
| nitro compounds/groups | II | Reactions of Benzene, Amines |
| nitrogen/amine (Walden) inversion | I | Stereochemistry |
| “Nitrogen Rule” | I | Mass Spectrometry |
| NMR | I | Nuclear Magnetic Resonance |
| node or nodal surface | I | Atoms and Orbitals |
| nomenclature | I | IUPAC Nomenclature |
| Non-first Order Coupling | I | NMR Spectroscopy |
| Non-first Order Splitting | I | NMR Spectroscopy |
| non-aromatic | II | Aromaticity |
| non-bonded electron pair | I | Mass Spectrometry |
| non-decoupled | II | C NMR Spectroscopy |
| nonpolar nolvent | II | Solvents |
| non-spontaneous reaction | I | Kinetics vs. Thermodynamics |
| nonsuperimposable (unmappable on itself) | I | Chirality |
| Nu: (nucleophile) | I | Reaction Mechanism, Lewis Bases |
| nuclear spin flip | I | NMR Spectroscopy |
| nucleic acids | II | Nucleic Acids |
| nucleophile | I | Reaction Mechanisms |
| Nucleophilic Aromatic Substitution | II | Reactions of Benzene II |
| nucleophilicity | I | Reaction Mechanism |
| nucleoside | II | Nucleic Acids |
| nucleotide | II | Nucleic Acids |
| Octet Rule (second row elements) | I | Bonding and Hybridization |
| olefin (alkene) | I | Alkenes |
| one equivalent (1 equiv.) (1eq.) | LAB | |
| One-Molecule-Rule | I | |
| optical activity | I | Chirality & Stereochemistry |
| optically inactive | I | Chirality & Stereochemistry |
| organometallic (organotransition metals) | I | Organotransition metal compounds |
| organolithium Reagent, RLi | I | Organometallics |
| ortho– (o-) | II | Reactions of Benzene |
| ortho/para directing group | II | Reactions of Benzene |
| -OMs (mesylate) | I | Alcohols |
| -OTf (triflate) | I | Alcohols; Amines, Oximes |
| -OTs (tosylate) | I | Alcohols |
| oxaphosphetaine | II | Ketones & Aldehydes |
| oxidant/oxidizing agent | I,II | Redox Reactions |
| oxidation | I,II | Electrophilic Addition, Redox |
| oxime | II | Ketones and Aldehydes |
| oxonium ion; oxocarbenium ion | II | Alkenes, Ketones and Aldehydes |
| oxyanion | I | Substitution |
| ozone (O3) | I | Redox Reactions, Alkenes, Alkynes |
| ozonolysis (Harries Reaction) | I | Redox Reactions, Alkenes, Alkynes |
| pi-(π) bond | I | Bonding and Hybridization |
| pi-(π) molecular orbital | I | Bonding and Hybridization |
| pi* (π*) molecular orbital | I | Bonding and Hybridization |
| p orbital / p character | I | Bonding and Hybridization |
| para- (1,4-) | II | Reactions of Benzene |
| paraffin | I | Alkanes |
| pentet | I | NMR Spectroscopy |
| peptide | II | Amino Acids and Proteins |
| peptide (amide) bond | II | Amino Acids and Proteins |
| peracetic acid (RCO3H) | I | Redox Reactions |
| peracid | I | Redox Reactions |
| percent (%) yield (Actual Yield) | LAB | |
| permanganate | I | Redox Reactions |
| peroxide (ROOR), peracid (RCO3H) | I | Radical Reactions |
| pH | I | Acids and Bases |
| pKa | I | Acids and Bases |
| pharmacology; pharacokinetics | II | Drugs and Enzymes |
| phenol (Organic II, Reactions of Benzene) | II | Alcohols; Reactions of Benzene |
| phenyl group (Ph-) | I | Nomenclature |
| Phenylalanine (Phe, F) | II | AminoAcids and Proteins |
| phospholipid | II | Fats and Lipids |
| phosphodiester | II | Nucleic Acids |
| photochemistry | II | Pericyclic Reactions |
| photolysis | II | Radical Reactions |
| photon (E = hv) | Gen | |
| pi-cation interaction | II | Secondary Spatial Effects |
| π-stacking | II | Secondary Spatial Effects |
| piperidine | II | Heterocycles |
| pKa | I | Acids and Bases |
| pKb | I | Acids and Bases |
| plane-polarized light | I | Chirality |
| polar covalent bond | I | Bonding and Hybridization |
| polar polvent | I | Solvents |
| polarimetry | I | Chirality |
| polarizability | GEN | |
| polypeptide | II | Peptides and Proteins |
| polysaccharide | II | Sugars |
| potential energy | I | Kinetics and Thermodynamics |
| ppm | I | NMR Spectroscopy |
| Pr- (propyl substituent) | I | Nomenclature |
| precipitate | LAB | |
| primary (1o) | I | Classifying Carbons |
| pro-drug | II | Drugs and Enzymes |
| product | I | Mechanism |
| Proline (Pro or P) | II | Peptides and Proteins |
| propagation | I | Radical Reactions |
| progargylic position | I | Resonance |
| Protection, Functional Group | I | Ketones and aldehydes |
| protecting groups | II | Protecting Groups |
| protein | II | Peptides and Proteins |
| protic solvent (H-bonding solvent) | I | Solvents |
| proton (H+) | I | Atoms and Molecules |
| proton 1H NMR | I | NMR Spectroscopy |
| protonation | I | Catalysis |
| p-toluenesulfonate | I | Substitution/Elimination |
| p-TsCl (para-toluenesulfonyl chloride) | I | Substitution/Elimination |
| p-TsOH (para-toluenesulfonic acid) | I | Substitution/Elimination |
| purine | II | Nucleic Acids |
| pyran | II | Alcohols, Ethers & Epoxides |
| pyridine (pyr.) | II | Aromatics |
| pyrimidine | II | Nucleic Acids |
| pyrrole | II | Aromaticity; Heterocycles |
| pyrrolidine | II | Heterocycles; Amines |
| QSAR (quantitative structure-activity relationships) | I | Electron Configuration |
| quantum numbers | I | Electron Configuration |
| quartet (q) | I | NMR Spectroscopy |
| quaternary Carbon (4o) | I | Classifying Carbon |
| quaternary structure | I | Peptides & Proteins; Enzymes |
| quintet | I | NMR Spectroscopy |
| R = Universal Descriptor | I | Nomenclature |
| R- Group (often alkyl) | I | Nomenclature |
| racemic | I | Stereochemistry |
| racemic mixture (racemate) | I | Stereochemistry |
| radical or free radical | I | Radicals |
| radical cation | I | Mass Spectrometry |
| rate-determining or rate-limiting or slow | I | Rxn Coord Diagrams |
| reactant | I | Mechanism |
| reaction coordinate diagram | I | Rxn Coord Diagrams |
| reaction coordinate (surface) | I | Mechanism |
| reaction mechanism | I | Organic Reactions |
| reactive oxygen species (ROS) | I | Radicals |
| reactivity-selectivity principle | I | Kinetics & Thermodynamics |
| rearrangements (as reactions) | I, II | Carbocations |
| reducing agent or reductant | I | Redox Reactions |
| reduction (reaction) | I | Redox Reactions |
| regioselectivity, regioselection | I | Regiochemistry |
| resolution – chiral; kinetic | I | Stereochemistry |
| resonance | I | Resonance I |
| resonance contributor/structure/mesomer | I | Resonance I |
| resonance forms, prioritization of | I | Resonance I |
| Retro-aldol | II | Ketones & Aldehydes |
| Retro Diels-Alder ([4+2] cycloreversion) | I | Dienes |
| Retrosynthetic Analysis/Retrosynthesis | I | Introduction to Synthesis |
| Ribonucleic Acid | II | Nucleic Acids |
| ribose | II | Nucleic Acids |
| Ring Flip – Chair-Boat-Chair Interconversion | I | Conformational Analysis |
| Ring Strain: Baeyer, Pitzer, Transannular | I | Conformational Analysis |
| RNA – ribonucleic acid | II | Nucleic Acids |
| sigma (σ) bond | I | Bonding and Hybridization |
| s orbital | I | Bonding and Hybridization |
| σ and σ* orbitals | I | Bonding and Hybridization |
| S (Lat. sinister) configuration | I | Stereochemistry |
| s-cis (s = single-bond) | I | Dienes |
| s-BuLi (s=sec) | II | Carbon Bases |
| s-trans (s = single-bond) | I | Dienes |
| Sanger’s Reagent | II | Nucleic Acid (Sequencing) |
| saponification (ester hydrolysis) | II | Carboxylic Acid Derivatives |
| saturated | I | Alkanes |
| sawhorse projection | I | Representing Organic Compounds |
| Saytseff’s Rule (Zaitzev’s Rule) | I | Elimination |
| Schiff Base (akylamine) | II | Ketones and Aldehydes |
| sec-butyl group | I | Nomenclature |
| secondary structure | II | Peptides and Proteins, Nucleic Acids |
| Serine (ser or S) | II | Peptides and Proteins |
| sextet | I | NMR Spectroscopy |
| side chain | I | Nomenclature |
| shielded (upfield), chemically | I | NMR Spectroscopy |
| single bond | I | Bonding and Hybridization |
| singlet (s) | I | NMR Spectroscopy |
| skeletal formula (line-angle) | I | Representing Organic Compounds |
| SN1 limiting mechanism | I | Substitution |
| SN2 limiting mechanism; SN2′ mechanism | I | Substitution |
| sodium borohydride (NaBH4) | I | Redox Reactions |
| sodium hydride (NaH) | I | Bases |
| solubility | I | Solvents |
| solute | I | Solvents |
| solvent | I | Solvents |
| solvent cage | I | Solvents |
| solvolysis/solvolytic | I | SN1 and E1 |
| sp orbitals/atoms | I | Hybridization |
| sp2 orbitals/atoms | I | Orbital Hybridization |
| sp3 orbitals/atoms | I | Orbital Hybridization |
| space-filling model | I | Representing Organic Compounds |
| specific rotation [αo] | I | Chirality |
| spectrometry | I | Structural Elucidation |
| spectroscopy | I | Structural Elucidation |
| spin quantum number | I | Electron Configuration |
| spin-spin coupling | I | Spectroscopy |
| spirocyclic ring | II | Polycyclic rings systems |
| splitting, nuclear (multiplicity in signals) | I | NMR Spectroscopy |
| spontaneous change/reaction | I | Thermodynamics |
| squiggly line bond | I | Representing organic compounds |
| staggered conformation | I | Newman Projections |
| starting material (substrate beginning a synthesis) | I | Reactions |
| stereocenter or stereogenic center | I | Chirality |
| stereochemistry | I | Stereochemistry |
| stereoselective | I | Chirality |
| stereospecific | I | Stereochemistry |
| steric effects | I | Stereoelectronics |
| steric hindrance | I | Conformational Analysis |
| steric number | I | Conformational Analysis |
| steric strain | I | Conformational Analysis |
| steroids | II | Lipids and Fats |
| stoichiometry | GEN | |
| stretching frequency [cm-1] | I | IR Spectroscopy |
| sublimation | GEN | (s) → (g) |
| substituent (any replacement for hydrogen) | I | Nomenclature |
| substitution Reaction (displacement) | I | Classes of reaction |
| substrate (reactant) | I | Mechanism |
| sucrose (disaccharide) | II | Sugars |
| suicide inhibitor/inhibition | II | Drugs, Enzymes, & Kinetics |
| sulfide (R-S-R) | I | Functional Groups |
| sulfonamide (-S(O2)ONR2) | II | Functional Groups |
| sulfonate ester (RSO3R) | I | Functional Groups |
| sulfonate anion (-RSO3-) | I | Functional Groups |
| sulfonic acid (RSO3H) | I | Functional Groups |
| sulfonation | II | Reactions of Benzene |
| sulfone (R-SO2R) | I | Functional Groups |
| sulfonic Acid | II | Functional Groups |
| sulfonyl chloride (thionyl chloride) | II | Substitution |
| sulfoxide (R-S(O)R) | I | Functional Groups |
| superimposable (superposable or mappable onto itself) | I | Chirality |
| suspension | GEN | |
| symmetric stretch | I | IR spectroscopy |
| syn or erythro configuration (rings or chains) | I | Modes of Addition |
| syn addition | I | Modes of Addition |
| syn-periplanar | I | Dihedral geometry |
| synthesis | I | Chemical Synthesis |
| t-BuLi | II | Organometallics |
| tautomer | I | Tautomerization |
| tautomerization | I | Tautomerization |
| t-Bu | I | tert-butyl |
| t-BuOH | I | t-butyl alcohol |
| terminal alkene | I | Alkenes |
| terminal alkyne | I | Alkynes |
| termination, of a chain reaction | I | Radical Reactions |
| termolecular (3rd order) | I | Electrophilic Addition |
| tertiary (3o | I | Classifying carbon |
| tetrahedral carbon (sp3 | I | Classifying carbon |
| tetrahedral intermediate | I | Carboxylic Acid Derivatives |
| tetrahydrofuran (THF) | I | Solvents |
| tetramethylsilane (TMS) | I | NMR Spectroscopy |
| tetrasubstituted | I | Alkene stability |
| theoretical yield | GEN | Lab |
| thermodynamic control/product | I | Kinetics vs. Thermodynamics |
| thioester | I | Functional Groups |
| thioether (sulfide, R-S-R’) | I | Functional Groups |
| thiol (thioalcohol; RSH; mercaptan) | I | Functional Groups |
| thiolate anion; RS– | I | Functional Groups |
| thiophene | I | Heterocycles |
| Threonine (Thr or T) | II | Peptides and Proteins |
| Thymine (T) | II | Nucleic Acids |
| titration | I | Acids and Bases |
| toluene (tol.) | I | Aromaticity |
| torsional strain | I | Conformational Analysis |
| tosylate (-OTs) | I | Substitution |
| trans– | I | Stereochemistry |
| transesterification | II | Carboxylic Acid Derivatives |
| transition metals | II | Organometallics |
| transition state | I | Reaction Mechanism |
| tricyclic | I | Polycyclic compounds |
| triflate (-OTf) | I | Super Leaving groups |
| triflic acid (HOTf, TfOH) | I | Substitution |
| triglyceride (Triacylglycerol) | II | Fats and Lipids |
| triose | II | Sugars |
| triple bond | I | Alkynes |
| triplet (t) | I | NMR Spectroscopy |
| triplet of doublets (td) | I | NMR Spectroscopy |
| trisubstituted | I | Alkenes |
| Tritium 3H | I | Mass Spectrometry |
| Tryptophan (Trp or W) | II | Peptides and Proteins |
| Two-Dimensional NMR | II | NMR spectroscopy |
| Tyrosine (Tyr or Y) | I | Peptides and Proteins |
| unimolecular kinetics | I | Kinetics |
| unsaturated / unsaturation | I | Fats and Lipids |
| upfield, chemically (shielded) | I | NMR Spectroscopy |
| Uracil (U) | II | Nucleic Acids |
| valence | I | Trends in the Periodic Table |
| Valence Bond Theory | I | Theory |
| valence electrons | I | Electron Configuration |
| valence shell | I | Electron Configuration |
| Valine (Val or V) | I | Peptides and Proteins |
| Van der Waals Forces | I | Intermolecular Interactions |
| Van ’t Hoff Rule | I | Stereochemistry |
| vapor pressure | LAB | |
| vaporization | GEN | |
| vicinal (1,2 or vic) | I | Nomenclature |
| vinyl group | I | Nomenclature |
| vinylic Position | I | Nomenclature |
| vitamin | II | Enzymes and Co-factors |
| VSEPR Guidelines | GEN | |
| Walden Inversion | I | Stereochemistry |
| Watson-Crick Base Pair | II | Nucleic Acids |
| wavenumber (cm-1) | I | IR Spectroscopy |
| wavy line (ambiguous configuration) | I | Representing Organic Compounds |
| wedge | I | Representing Organic Compounds |
| Williamson Ether Synthesis | I | Named Reactions |
| Wittig Reaction | II | Ketones and Aldehydes |
| Wolff-Kischner Reduction | II | Redox Reactions |
| % percent yield (actual yield) | LAB | |
| ylide (or ylid) | II | Ketones and Aldehydes |
| Z (Ger. Zussamen) olelins, esters, enolates | I | Stereochemistry |
| Zaitsev’s Rule | I | Elimination |
| zig-zag Structure (see line-angle) | I | Drawing Organic Structures |
| zwitterion (‘w’ pronounced as ‘v’) | II | Peptides and Proteins |
Organic-ese Organic Chemistry
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