CHEM 261

Introduction to Organic Chemistry

Arene

Aromatic ring

Haloalkane

C-X (x= halogen)

Alcohol

C-OH

Ether

C-O-C

Aldehyde

Ketone

Carboxylic Acid

Ester

Acid Halide

Anhydride

Amide

Amine

Primary Carbon

1 substituent on carbon

Secondary Carbon

2 substituent on carbon

Tertiary Carbon

3 substituent on carbon

Quaternary Carbon

4 substituent on carbon

Covalent Bonding

Sharing of electrons between atoms

SP³ Hybridization

tetrahedron, bond angles are 109°

SP² Hybridization

planar, bond angles are 120° (double bond)

SP Hybridization

linear, bond angles are 180° (triple bond)

Steroid Molecule

Decane

C10H22

Undecane

C11H24

Dodecane

C12H26

Tridecane

C13H28

Tetradecane

C14H30

Pentadecane

C15H32

Hexadecane

C16H34

Heptadecane

C17H36

Octadecane

C18H38

Nonadecane

C19H40

Eicosane

C20H42

Triacontane

C30H62

Tetracontane

C40H82

Pentacotane

C50H102

Hexacotane

C60H122

Structural isomer

same molecular formula as another molecule but a different arrangement

Stereoisomer

same molecular formula and connectivity of atoms but different three-dimensional arrangement of atoms

Chemistry

Study of matter

Organic Chemistry

Study of compounds containing carbon

Atomic Number

Number of protons in the nucleus of an atom (Z)

Atomic Weight

Mass of protons (p+) and neutron (n) (unit: amu)

Molecular Weight

Mass of atoms in a molecule

Isotopes

same element that contain equal number of protons but different number of neutrons

s-Orbital

Spherical shaped cloud of electrons (electron density)

p-Orbital

Dumbbell-shaped cloud of electrons (Three orientations: placed on the x, y and z-axis)

Isoelectronic

same electronic structure

Ionic Bonding

positive and negative species are bonded to each other

Hybridization

Mixing of atomic orbitals (with the wrong geometry for bonding) to form hybrid orbitals with the correct geometry for bonding

sigma orbital

molecular wave function (orbital) made by linear combination of atomic orbitals having an s component

enthalpy

bond energy

pi orbital

molecular wave function (orbital) made by linear combination of two p atomic orbitals

electronegativity

desire (attraction) of an atom for electrons (negative charge)

London forces

intermolecular attraction due to temporary dipoles

Lewis acid

A substance that can accept a pair of electrons

Methyl Group

CH3

Methylene Group

CH2

Methine Group

CH

Decalin

Methylene Chloride

Chloroform

CHCl3

Cholesterol

Norbornane

Chiral

has a non-superimposable mirror image

Achiral 

not chiral, has a superimposable mirror image

Diastereomers

all stereoisomers that are not enantiomers

Anti Staggered

favoured, lowest energy

Staggered Gauche

Syn Eclipsed

Adamantane

Diatomic molecules

F, Cl, Br, I

Hemolytic

One electron goes to each atom once the bond in broken. e.g. Free radical halogenation of alkanes

Heterolytic

(polar reaction): The electron pair goes to one of the atoms once the bond is broken. e.g. Addition reactions of alkenes; elimination reactions

Mechanism of Halogenation

Hammonds Postulate

For an exothermic reaction, the transition state is closer in energy to the reactants and thus resembles them structurally. Conversely, for an endothermic reaction, the transition state is closer to the products in energy and has a structure that resembles them 

Resolution

separation of enantiomers

Enantiomers

molecules that are stereoisomers and are non-superimposable mirror images of each other. Opposite stereochemistry at every chiral center.

Fischer Projection

A method of drawing chemical structures, where the horizontal components are coming towards you and the vertical ones are going back.

Meso Compounds

stereogenic centers but contain a plane of symmetry and are achiral

SN1

rate depends on 1 concentration

SN2

The rate is dependent on the concentration of the nucleophile and the electrophile (2 concentrations)

Stereospecific

stereochemistry of the starting material determines the stereochemistry of the product.

Concerted

The bonds of the starting material break at the same time as the product bonds form.

isopropyl chloride

neopentane

Vinyl

Allyl

Phenyl

Benzene

Benzyl

Toluene

Phenol

R, Rectus

stereocenter that is right-handed, clockwise

S, Sinister

stereocenter that is left-handed, counterclockwis

Olefin

Another name for alkene

acetylene

Another name for alkyne

E

Entegegen - Opposite

Z

Zusammen - Together

Isoprene

Terpenes

Natural products containing alkenes (units of C5)