Chapter 10.1: Organic chemistry fundamentals Isomers Review: Types of carbon atoms: primary, secondary, terTiary Saturation of hydrocarbons

Physical property trends of organic molecules Overall, organic compounds are made of two parts: Hydrocarbon skeleton (framework) Differs in size in members of same homologous series meth-, eth-, prop-, etc. Functional group Differs in type in different homologous series -OH, -COOH, -CHO, etc. Know the trends of bonding from chapter 4 AND: Increase in #C = increase in B.P. Branching of chain = decrease in IMFs  decrease in M.P.

In some cases, it is necessary to insert a number into the name to indicate which carbon the functional group is joined to. Example: Both of these molecules could be described as butene. But they are not identical . . . . what is the difference? What would be the name of each according to IUPAC conventions? Both have exact molecular formula ( C4H8 ) but are not identical. Isomers: compounds with the same molecular formula but a different arrangement of atoms.

Isomers Isomer: compounds with same molecular formula but different atomic arrangements

Structural Isomers Structural isomers: same molecular formula, but different arrangement of atoms Ex. C4H10 Draw the isomers for C6H14 How many are there? Can you name them?

Structural Isomers Structural isomers: same molecular formula, but different arrangement of atoms Each isomer is unique and has individual chemical and physical properties Larger the molecule, the more isomers! C7H16

Structural Isomers – alkanes C4H10 has how many isomers? Draw them Name them C5H12 has how many isomers? C6H14 has how many isomers? Check your work on page 473-474!

Structural Isomers – alkenes C4H8 has how many isomers? Draw them Name them C5H10 has how many isomers? C6H12 has how many isomers? Check your work on page 475! The same process can be used for alkynes!

Structural Isomers – 1°, 2°, 3° carbons Carbons can also be primary, secondary and tertiary

Degree of unsaturation – index of hydrogen deficiency (IHD) Page 553 (chapter 11.3) IHD: A measure of how many H2 molecules, in theory, are needed to convert a molecule to the corresponding saturated, non-cyclic molecule

Arenes AKA aromatics Class of compounds derived from benzene (C6H6) Called aromatics Aromatics have the phenyl/benzene ring, Aliphatics are non-aromatic Include other cyclo-compounds Aromatic or aliphatic?

Arenes - benzene Benzene does not behave like other unsaturated molecules Double bonds can undergo addition RXNs (adding something to double bond) BUT, benzene does not like to undergo this kind of RXN High degree of unsaturation (has 3 double bonds) The molecule is symmetrical Has no isomers Why so special?

Arenes - benzene Delocalized electrons are responsible for the stable, relatively unreactiveness of benzene Know: hybridization of C, # of σ and π bonds, angle, shape Use:

Properties of Benzene You should know the properties of benzene (p. 480-1)

Arenes - benzene

Properties of Benzene continued