Tips for Organic Chemistry Success In order to successfully understand the various types of Organic molecules you should be able to identify each of the following for each type of molecule: Structural characteristics (know the functional group) Nomenclature (the rules for naming the molecules) Physical and Chemical properties (basic/simple) Occurrence and uses (common) Preparation (what basic reactions produce the molecules) Characteristic reactions of the molecules For additional help, check out the Organic Chemistry section of the following website:

Organic vs. Inorganic Compounds Inorganic compounds: cpds which are NOT hydrocarbons (~1.5 million) Organic compounds: cpds which contain hydrogen & carbon (thus, hydrocarbons & derivatives) (~ 7 million) “Organic Chemistry” started, as a branch of chemistry, when F. Wohler disproved the idea of “vital force.” - previously, it was thought that there were two types of matter (based on heating): melting/freezing cooking (required “vital force”)

Carbon Atoms Carbon atoms generally form 4 bonds (think about their electron configuration) In “organic” compounds these bonds are typically COVALENT. Carbon readily forms bonds with other carbon atoms as well as with atoms of other elements. Carbons w/ H’s attached are known as alkyl groups. -CH 3 methyl -CH 2 CH 3 ethyl

Hydrocarbons & their Derivatives Hydrocarbons: H & C atoms only (the C & H atoms form the backbone of all organic molecules ) Derivatives: H, C & other elements Saturated Hydrocarbons: all C-C bonds are “single.” –Alkanes and their derivatives Unsaturated Hydrocarbons: one or more C-C bond(s) is/are multiple. –Alkenes, alkynes, aromatics & their derivatives

Basic Structural Features Chains of atoms Rings of atoms

Shapes of Organic Molecules The # of effective e - pairs around a center atom will determine the geometry of the molecule. # e - pairse - pair geometry 2 pairslinear 3 pairstrigonal planar 4 pairstetrahedral Remember, the e - pair geometry and the molecular geometry are NOT necessarily the same!

Drawing Organic Molecules Complete Structures: draw all atoms and all bonds, showing relative shapes Condensed Structures: write each alkyl (CH x ) group separately. Skeletal Structures: carbon atoms at each line junction, assume enough H’s; draw all heteroatoms & their H’s.

Naming Organic Molecules The number of carbons in a chain is identified according to the following: –# Cname beginning 1meth- 2eth- 3prop- 4but- 5pent- 6hex- 7hept- 8oct- 9non- 10dec- The end of the name is based on C-C bonding: –All single C-C bonds - end in “-ane” –One or more double C-C bonds end in “-ene” –One or more triple C-C bonds end in “-yne”

Functional Groups Functional groups contain a heteroatom, a multiple bond, or both and provide characteristic chemical & physical properties. Abbreviating the hydrocarbon backbone: R - fcn’l grp ex.R - Bralkyl halide R - OHalcohol (-OH is hydroxyl group) R - COOH carboxylic acid (-COOH is carboxyl group)

Single vs. Double bonds to Heteroatoms Single –Alkyl halides –Alcohols –Ethers –Amines Double (-C=O, carbonyl) –Aldehydes –Ketones –Carboxylic Acids –Amides –Esters

Properties of Organic Cpds Polarity of molecule is determined by electronegativity differences and shape of molecule. Solubility: most are soluble in organic solvents water solubility is based on size of molecule & polarity.

Pollutants Organic pollutants affect the environment depending on their solubility. Ex.DDT (dichlorodiphenyltrichlorothane) Crude Oil

Vitamins Water soluble: –Lots of polar bonds & polar fcn’l groups –Typically smaller molecules –C and all the B’s Water insoluble: –Lots of nonpolar bonds and few polar fcn’l groups –Typically larger molecules –A, D, E, K