Unit 15: Organic Chemistry

What is organic chemistry? The study of carbon and carbon-containing compounds

A Review of the Carbon Atom

A Review of the Carbon Atom Forms 4 covalent bonds Has 4 valence electrons, needs 4 more Carbon can form single OR multiple covalent bonds with other elements and other carbon atoms

Properties of Organic Compounds most are insoluble in water (generally non-polar) Remember- likes dissolve likes most are poor conductors Weak IMFs, so they have low m.p./b.p. Tend to have longer reaction times

Types of Organic Compounds Alkanes: contain all single carbon-carbon bonds Formula: CnH2n+2 Alkenes: contain at least one double carbon-carbon bond Formula: CnH2n

Alkynes: contain at least one triple carbon-carbon bond CnH2n-2

More on Alkanes….

Alkanes Can be straight or branched All names of alkanes end in –ane Are saturated hydrocarbons, meaning they contain the max. number of hydrogen atoms per carbon atom

Straight-Chained Alkanes Prefixes identify the # of carbon atoms in the chain (use Table P) Examples:

Branched Alkanes -CH3 methyl -CH2CH3 ethyl -CH2CH2CH3 propyl An atom or a group of atoms that replaces a C-H bond and forms a branch is called an alkyl group -CH3 methyl -CH2CH3 ethyl -CH2CH2CH3 propyl -CH2CH2CH2CH3 butyl

Alkenes End in –ene Are unsaturated compounds- do not contain the max. # of hydrogen atoms per carbon atom Examples:

Alkynes End in –yne Also unsaturated compounds Examples:

Per. 8 and 6- Monday, 6/1 I will not be after school today Extra Credit due Friday Chemistry Calculations WS due Friday (Part 2 #4) Organic Test next Monday

Isomers Compounds that have the same molecular formula, but different structural formulas and different names Isomers have different chemical & physical properties At least 4 carbons must be present in a molecule to have potential isomers

3 Ways to Make an Isomer Make a branch Move a branch Move a double or triple bond

Example 1 Draw 3 isomers of pentane

Example 2 Draw 3 isomers of butene

Functional Groups (Table R) Something other than carbon and hydrogen in an organic compound ** Compounds with the same functional group have similar chemical properties

1. Halides A halogen (group 17 elements such as F, Cl, Br, I) replaces a hydrogen atom in an alkane

2. Alcohols One or more of the H’s is replaced by an –OH group “-e” ending on hydrocarbon is replaced by “-ol” Remember: alcohols are NOT bases, they are covalent molecules

3. Ethers look for -O- bridging two hydrocarbon chains Name pieces on either side of O and end with ether

4. Aldehydes Double bonded oxygen and a hydrogen off the end of a carbon chain **Ending: drop the –e and add –al No need for a number

5. Ketones Double-bonded oxygen in the middle of a carbon chain Drop the –e and add –one Number position of the oxygen

6. Organic Acid COOH group at the end of a chain **Ending: drop the –e and add –oic acid No need for a number

7. Ester -COO- group in the middle of a chain Change ending to -oate

8. Amines -NH2 group added to a carbon chain Drop the –e and add –amine Add number for which C atom contains the amine

9. Amides -CONH2 group at the end of a chain Ending: drop the –e and add –amide