Chapter 1 Organic Chemistry Chemistry 20

Organic Compounds

Chemistry of Carbon (H, O, N, S, Halogens, and P). H: 0.9% Ti: 0.6% Others: 0.9% C one of the 116 elements

Obtained by: Isolation from nature (animal and plant) Synthesis in lab Organic compounds: 10 million Inorganic compound: 1.7 million Compounds in living systems are organic: Biochemistry Organic Compounds (extract-isolate-purify)

Organic Compounds First organic compound that is synthesized in lab. Wöhler (1828)

Organic Compounds Typical organic compounds: Contain carbon Have covalent bonds Have low melting points Have low boiling points Are flammable (all burn) Are soluble in nonpolar solvents May be gases, liquids or solids C 3 H 8 Propane

Organic Compounds

shows the atoms present in a molecule as well as the bonds that connect them. Structural Formula (Lewis Structure)

VSEPR Model VSEPR: Valence-Shell Electron-Pair Repulsion method Bond angle: angle between two atoms bonded to a central atom. Each region of electron likes to be as far away as possible from the others.

Regions of electron density Four regions of electron density around an atom:

Bond Angles & Geometric Structures Linear molecules Trigonal planar molecules Tetrahedral arrangement 2 regions 3 regions 4 regions

Tetrahedral Electron Pair Geometry (Tetrahedral arrangement)

H2OH2OCH 4 NH 3 Tetrahedral Electron Pair Geometry Unshared electron paires

–Carbon: normally forms four covalent bonds and has no unshared pairs of electrons. –Hydrogen: forms one covalent bond and no unshared pairs of electrons. –Nitrogen: normally forms three covalent bonds and has one unshared pair of electrons. –Oxygen: normally forms two covalent bonds and has two unshared pairs of electrons. –A Halogen: normally forms one covalent bond and has three unshared pairs of electrons. C H N O = Cl......

An atom or group of atoms within a molecule that shows a characteristic set of predictable physical and chemical properties. –A way to classify organic compounds into families. –They determine the chemical and physical properties of a compound. –They undergo the same types of chemical reactions. –A way to name organic compounds. Functional groups

Alkanes: contain single bonds between carbon atoms. Alkenes: contain one or more double bonds. Alkynes: contain one or more triple bonds. Alkanes, Alkenes, and Alkynes C C C C C C

Alcohols and Ethers C C C C O O H Alcohols: contain the hydroxyl (-OH) functional group. Ethers: an oxygen atom is bonded to two carbon atoms. C O C

Aldehydes: contain a carbonyl group (C=O), which is a carbon atom with a double bond to an oxygen atom. Ketones: the carbon of the carbonyl group is attached to two other carbon atoms. Aldehydes and Ketones O O CC C C C H

Carboxylic acids: contain the carboxyl group (-COOH), which is a carbonyl group attached to a hydroxyl group. Esters: the hydroxyl group of a carboxylic acid is replaced by a carbon atom. Carboxylic acids and Esters O O O O C C C C H

Amines: the functional group is a nitrogen atom. | — N — Amides: the hydroxyl group of a carboxylic acid is replaced by a nitrogen group. Amines and Amides O C C C C N N N NR