Glossary of Organic Chemistry Jargon and Acronyms

This is an alphabetical listing of some common jargon words, slang, and acronyms used in organic chemistry. Have a suggestion for this list? Please send us a note on the Contact page.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P
Q | R | S | T | U | V | W | X | Y | Z | Numbers, Greek Letters, Symbols

A

Ac
Acetyl
Acryloyl
2-propenoyl; the CH2CHCO group
Ad
Adamantyl
Allene
An olefin connected directly to another olefin so that the carbon in the middle is double bonded to both of the carbons next to it (that is, as C=C=C).
Allyl/Allylic
On the α-carbon of an olefin.
Anh.
Anhydrous
Anti
On opposite sides
Analytical
In chromatography, the scale at which only enough oif a mixture is separated so that each compound can be analyzed spectroscopically. Compare with Preparatory
aq
Aqueous
Ar
Any generic aromatic group (e.g. Phenyl, Benzyl, Napthyl, etc.)
ATP
Adenosine triphosphate

B

BINAP
2,2'-(bisphenylphosphino)-1,1'-binaphthyl
Bn
Benzyl
Boc
tert-butoxycarbonyl
BOM
Benzyloxymethyl
Bu
Butyl

C

C2
180° rotational symmetry about some axis (usually of a molecule)
Carbon tet
Carbo tetrachloride
CBS
Corey-Bakshi-Shibata oxazaborolidine
Cbz
Benzyloxycarbonyl
cHex
See Cy
Cinnamic
The PhCH=CHCO- group
Cis
For doubly substituted double bonds, the two substituents are on different carbons and on the same side
Cp
Cyclopentadienyl
CSA
Camphorsulfonic acid
Cy
Cyclohexyl
Cyhex
See Cy
Cyp
See Cp

D

DABCO
1,4-diazabicyclo[2.2.2]octane
DBU
1,8-diazabicyclo[5.4.0]undec-7-ene
DCC
Dicyclohexylcarbodiimide
DCM
Dichloromethane
DDQ
2,3-dichloro-5,6-dicyano-1,4-benzoquinone
de
Diastereomeric excess
DEAD
Diethyl azodicarboxylate
DIBAL/DIBAL-H
Diisobutylaluminum Hydride
DIEA
Diisopropylethyl amine (Hunig's Base)
DIPEA
See DIEA
DMAP
N,N-dimethylaminopyridine
DMF
N,N-dimethyl formamide
DMP
Dess-Martin periodinane
DMPU
N,N'-dimethylpropyleneurea
DMS
Dimethyl sulfide
DMSO
Dimethyl sulfoxide

E

ee
Enantiomeric excess
El
Electrophile
Endo
Opposite of exo, the orientation of reactants in a pericyclic reaction such that the substituents on the two reacting fragments overlap the most.
Et
Ethyl
Exo
Opposite of endo, the orientation of reactants in a pericyclic reaction such that the substituents on the two reacting fragments overlap the least.

F

FID
Free induction decay; the raw data from FTNMR spectroscopy, which gives chemical shift data after a Fourier-transform
Flash
Flash chromatography
Fmoc
9-flourenylmethoxycarbonyl
FTIR
Fourier-transform infrared spectroscopy
FTNMR
Fourier-transform nuclear magnetic resonance spectroscopy

G

H

Hetero-
(Prefix) (1) Involving a heteroatom at a key reactive position in place of a usual carbon atom, e.g. Hetero-Diels Alder; (2) involving different components (e.g. heterodimer); (3) Not the same all throughout (e.g. heterogeneous).
Heteroatom
Any non-carbon atom substitutent, usually non-metal, non-halogen species (but not always).
Heterocycle
A cyclic, often aromatic compound with a heteroatom as a key ring atom.
Heterodimer
A compound composed of two different subunits; technically, a misnomer, as dimer refers to what is sometimes called the homodimer
HMPA
See HMPT
HMPT
Hexamethylphosphorotriamide, hexamethylphosphoric triamide; sometimes, hexamethyl phosphine triamide
Homo-
(Prefix) (1) Different from the root word by an extra methylene group, usually in the middle of a hydrocarbon chain; (2)involving the same components (e.g. homodimer); (3) The same throughout (e.g. homogeneous).
HOMO
Highest occupied molecular orbital
Homodimer
A compound composed of two identical subunits; technically, a misnomer, as dimer refers to the same thing
Homology
A process in which a methylene group is added to the molecule
HPLC
High pressure liquid chromatography or high performance liquid chromatography
Hygroscopic
Water absorbing. Very hygroscopic compounds can absorb humidity out of the air

I

Im
See Imid
Imid
Imidazole
IPA
Isopropyl alcohol
iPr
Isopropyl
IR
Infrared spectroscopy

J

K

KAPA
Potassium 3-aminopropyl amide

L

LAH
Lithium aluminum hydride
LCAO
Linear combination of atomic orbitals
LDA
Lithium diisopropylamide (lithium diisopropylamine)
L-Selectride
Lithium tri-sec-butylborohydride
LTEAH
Lithium triethoxyaluminohydride
LUMO
Lowest unoccupied molecular orbital
Lut
2,6-lutidine

M

MALDI
Matrix-Assisted Laser Desorption/Ionization (Mass spectrometry); a way to ionize large molecules for mass spectroscopy using a laser-active chemical
MassSpec
Mass spectrometry
MC
Methylene chloride (See DCM)
MCPBA
Meta-chloroperbenzoic acid (3-chloro peroxybenzoic acid)
Me
Methyl
Mes
Mesityl (3,4,5-trimethylphenyl)
Methylene
A -CH2- group
MO
Molecular orbital, or Molecular orbital theory
mol%
Molar %; a reactant used at 10 mol% is used with 0.1 equivalents compared to the reference reactant or substrate
MOM
Methoxymethyl
MPLC
Medium pressure liquid chromatography
MRI
Magnetic resonance imagining; the use of NMR to image biological materials
Ms
See Mes
MS
Mass spectrometry
MTM
Methylthiomethyl
MVK
Methyl vinyl ketone

N

NAD
Nicotineamide Adenine Dinucleotide (Oxidized form of NADH)
NADH
Nicotineamide Adenine Dinucleotide Hydride (Reduced form of NAD)
NADP
Nicotineamide Adenine Dinucleotide Phosphate (Oxidized form of NADPH)
NADP
Nicotineamide Adenine Dinucleotide Phosphate Hydride (Reduced form of NADP)
NBS
N-bromosuccinimide
nBu
n-Butyl
NCS
N-chlorosuccinimide
NIS
N-iodosuccinimide
NMM
N-methylmorpholine
NMR
Nuclear magnetic resonance spectroscopy
Np
Naphthyl
nPr
n-Propyl
Nu
Nucleophile

O

OAc
Acetate
Olefin
A carbon-carbon double bond
OTf
Triflate (See Triflyl)

P

PCC
Pyridinium chlorochromate
PG
Any protecting group (e.g. TMS, TBS, Bn)
Ph
Phenyl
Phase
Can refer to either solid, liquid, and gas phases, or phases with regards to the separation of oils and aqueous liquids (e.g. aqueous phase)
Pr
Propyl
Prep or Preperatory
In chromatography, the scale needed to isolate compounds for further experiments. A larger scale than for analytical chromatography.
Pyrophoric
Ignitable when exposed to air

Q

R

R
(1) In a chemical diagram, any arbitrary functional group; (2) For a tetrahedral stereocenter, the configuration of bonds such that with the lowest priority group in the back, the priority order for the remaining three substituents from highest to lowest proceeds in a clockwise fashion (the same direction as "right" on a steering wheel).
rbf
Round-bottom flask
Rf
Retention factor; in TLC, the ratio of the distance the spot has moved from the baseline to the distance the solvent/eluent has gone

S

S
For a tetrahedral sterocenter, the configuration of bonds such that with the lowest priority group in the back, the priority order for the remaining three substituents from highest to lowest proceeds in a counter-clockwise fashion.
sBu
sec-Butyl
Sep Funnel
Separatory funnel
SOMO
Singly-occupied molecular orbital
Syn
On the same side

T

TADA
Transannular Diels-Alder reaction
TBAF
Tetrabutyl ammonium flouride
TBDPS
t-Butyl diphenyl silyl
TBS
t-Butyl dimethyl silyl
t-Bu
tert-Butyl
TEA
Triethylamine
TES
Triethyl silyl
TFA
Trifluoroacetic acid
Tf
See Triflyl
THF
Tetrahydrofuran
THP
Tetrahydropyran
TIPS
Triisopropylsilyl
TLC
Thin-layer chromatography
TMS
Trimethylsilyl
Tos
See Tosyl
Tosyl
Toluene-sulfonyl
Tr
See Trityl
Trans
For doubly substituted double bonds, the two substituents are on opposite sides and on different carbons
Transannular
An intramolecular reaction that occurs across a (usually large) ring
Triflyl
Triflouromethyl sulfonyl
Trityl
Triphenyl methyl
Ts
See Tosyl
TS
Transition state

U

V

Vinyl
Bonding directly to a double bond

W

X

Y

Z

Z
See Cbz

Numbers, Greek Letters, Symbols

9-BBN
9-borabicyclo[3.3.1]nonane
α or Alpha
Referring to the first atom or group away from some reference point (e.g. α-carbon refers to the carbon right next to the atom one is discussing). The subsequent substituents are named ascending the Greek letter scale (β, γ, &delta, and so on).
α-helix (Alpha-helix)
A helical coil of amino acids that have hydrogen bonds between every fourth amino acid residue
β-sheet (Beta-sheet)
An arrangement of amino acid chains such that each chain is H-bonded to the two chains next to it
χ (Chi)
A chiral auxiliary group, often (but not limited to) the Evans chiral oxazolidinone group
χn
A chiral auxiliary derived from R-valine (Note: n is almost a mirror image of v, which is the source of the notation; see the entry for χv
χp
A chiral auxiliary derived from L-phenylalanine; see the entry for χ
χq
A chiral auxiliary derived from R-phenylalanine (Note: q is nearly a mirror image of p, which is the source of the notation; see χp)/dd>
χv
A chiral auxiliary derived from L-valine; see the entry for χ
Φ (Phi)
(1) In a chemical diagram or formula, usually a phenyl group (the same as Ph) or a substituted phenyl group; (2) In physical chemistry or quantum mechanics, usually refers to a wavefunction or orbital that represents the behavior of the electrons in a system. ψ (psi) is also used.
ψ (Psi)
In physical chemistry or quantum mechanics, usually refers to the wavefunction or orbital that represent the behavior of the electrons in a system. Sometimes also φ (phi).
[H]
Reduction
[O]
Oxidation
Of or relating to a transition state