Organic Chemistry – the study of the carbon and carbon compounds. In organic compounds, carbons bond together to form chains, branches, rings and networks.

Carbon has four valence electrons and can form four bonds. These bonds can be single, double or triple. Remember: Single bonds:2 electrons shared Double Bonds: 4 electrons shared Triple Bonds: 6 electrons shared

1. Mostly non-polar, most organic compounds are insoluble in water. 2. Molecules are held together by very weak I.M.F. 3. Most organic compounds have very low melting points. They also have very high vapor pressure (evaporate easily). This is all due to the poor forces of attraction that hold the molecules in the sample together.

4. Organic compounds undergo combustion reactions. Combustion reactions follow the same template: Hydrocarbon + O 2  CO 2 + H 2 O These reactions are highly exothermic and release a lot of energy.

5. Organic compounds are poor conductors because they do not dissociate into ions. (nonelectrolytes) When organic compounds react, the reactions proceed much slower.

The following compounds are all known as hydrocarbons: made up of hydrogen and carbon atoms. Table Q shows us the three major groups of hydrocarbons:

Table P shows us how to assign the prefix of the name, depending on the number of carbons.

Practice Questions: 1.Which compound belongs to the alkene series? A) C 2 H 2 B) C 2 H 4 C) C 6 H 6 D)C 6 H What is the total number of electron pairs in a molecule of ethyne? A)1 B) 2C) 3D) 4 3.What is the total number of hydrogens atoms in a molecule of butene? A) 10 B) 6 C) 8D) 4

Using Table P and Q to determine the type of hydrocarbon: -Count up the number of carbons and hydrogens -Use Table Q to determine which family it belongs to: assign suffix -Use Table P to assign prefix Example: C 4 H 6 : Butyne

You can use Table P and Q to name simply hydrocarbons if you are given the molecular formula or the structural formula: C 5 H 10 C 3 H 4 C 2 H 6

Hydrocarbons can also be classified as saturated or unsaturated. Saturated: All single bonds between carbons atoms: Alkane Unsaturated: double or triple bonds between carbon atoms: alkene, alkyne.

Types of Formulas: Molecular formula: gives you the ratio of atoms Example: C 3 H 8 Structural formula: diagram or drawing of the compound Condensed Structural formula: each carbon group is written, separated with a line. CH 3 – CH 2 – CH 3

Ways to represent hydrocarbons

Alkanes: -Use Table P and Q to determine the number of carbons and hydrogens. -Connect all carbons with single bonds (saturated) -Add appropriate number of hydrogens, keeping in mind that each carbon needs 4 bonds.

Example: Write the formula and draw the following molecules: Ethane: Pentane: Octane: C2H6C2H6 C 5 H 12 C 8 H 18

Example… Name the following compound: Answer: Nonane

Alkenes: -Use Table P and Q to determine the number of carbons and hydrogens. -After propane, a number must be used to indicate where to put the double bond. -Numbering occurs either R  L or L  R, depending on which direction gives you the lowest possible number. -Add appropriate number of hydrogens, keeping in mind that each carbon needs 4 bonds.

Ethene Molecular Formula: C 2 H 4 Structural Formula: Condensed Structural formula: H 2 C = CH 2

Propene Molecular Formula: C 3 H 6 Structural Formula:

2-Butene Molecular Formula C 4 H 8 Structural Formula: Carbon-Carbon double bond is located after the 2 nd carbon: Condensed: CH 3 -CH-CH-CH 3

1-Butene Molecular Formula C 4 H 8 Structural Formula: Carbon-Carbon double bond is located after the 1 st carbon: Condensed: CH 2 -CH-CH 2 -CH 3

Alkynes: Repeat the process used for alkenes, but instead of adding a double bond: add a triple bond.

Ethyne Molecular Formula: C 2 H 2 Structural Formula: Condensed: CH-CH

Propyne Molecular Formula: C 3 H 4 Structural Formula: Condensed: CH-C-CH 3

2-Butyne Molecular Formula = C 4 H 6 Structural Formula:

Branched Hydrocarbons Can be thought of as having two parts: the main chain (backbone) and the alkyl groups (branches). -Name the longest unbroken chain of carbons. -Name the shorter alkyl groups and add “yl” to them. -Indicated which carbon each branch is located on, keeping lowest possible numbers.

Example: Find the longest chain: Find the alkyl group Where is the alkyl group: Put it all together: Pentane Methyl 3 rd Carbon 3- methyl pentane

Example Name: 2 methyl butane

Example: Step 1: Find the longest chain: Step 2: Number the carbons so the attached groups have the lowest possible numbers *2 and 4 are better than 4 and 6, so the chain should be numbered from L  R* Heptane

Step 3: Match up the numbers with the alkyl branches: 2-methyl 4-ethyl heptane Ethyl Methyl

Step 4: List alkyl groups in alphabetical order 4-ethyl 2-methyl heptane Ethyl Methyl

Step 5: Use IUPAC naming and punctuation: - Commas separate numbers listed together - Hyphens separate words and numbers Name: 4-ethyl 2-methylheptane Ethyl Methyl

Other IUPAC Naming Conventions: If the same alkyl group appears in two different places, use prefixes: If it appears 2x: “di” 3x: “tri” 4x: “tetra” 5x: “penta”

Other IUPAC Naming Conventions: Instead of 3-methyl 4-methyl hexane: 3,4-dimethylhexane

Example Name: 2,2-dimethyl propane

Example… Name the following 3-methyl pentane

Example… Name the following 3-ethyl pentane

Example…Draw the following: 2,3-dimethyl butane

Isomers As the hydrocarbons get larger and larger, they can form isomers Isomers are compounds that have the same molecular formula, but they have a different structural formula (arrangement) with different properties.

The following compounds both have the molecular formula: C 4 H 10 However, they have different structures, names and properties. 2- methyl propane Butane

As the number of carbon atoms increases the number of isomers increase as well. As the compounds get larger and larger, the more and more carbon atoms there are, the more isomers are possible.

They will not have the same name, they will look different but they have the same MOLECULAR FORMULA.

Example: Draw and isomer of heptane First, you must determine how many carbons/hydrogens you have to put together. Heptane = C 7 H 16 If we look at what heptane looks like, we can think about rearranging it to form something with a different structure.

One common way to create an isomer, is to shorten the chain by moving carbons inside to become branched groups.

For alkenes/alkynes: When the double or triple bond is located in a different place, this qualifies as an isomer.

We have only skimmed the surface of organic compounds. There are millions of organic molecules… and most of them are considered “substituted hydrocarbons.” This means that in addition to a chain of hydrogen and carbons, there are other atoms attached to the main chain. These are called functional groups. We need a consistent system on how to name them. These are IUPAC rules for naming organic compounds.

Table R should be used a model for you to use to name and draw these compounds. If you know how to use Table R, you will be able to successfully identify compounds, name them appropriately and even draw them.

Halides or “Halocarbons” Remember from our periodic table study, that the group 17 elements are the halogens. When we attach one or more of these elements, the resulting hydrocarbon is called a halide or halocarbon. Halogens = Group 17 elements: F, Cl, Br, I

Table R tells us: - what prefix to use for each halogen - to use a number to indicate the location of the halogen

Example: Chloroethane Why no number? Because if the Chlorine was on the other carbon, it would still be 1- chloroethane. 1

Name the following: 1,2-dibromopropane

Draw the following: 1,2-difluroethane

Alcohols Functional Group: OH This is different OH than the OH - hydroxide ion that we saw in Arrenhius’ bases. This OH is covalently bonded, so it does not dissociate into OH- ions.

Alcohols The OH group on the hydrocarbons makes one end of the molecule slightly polar. –This allows smaller alcohols to be dissolved in polar solvents like water This OH is covalently bonded to the carbon, so it doesn’t ionize in water. So it doesn’t make the solution basic

Alcohols Table R tells us: - Name the main chain - Add “ol” suffix - Use number to indicate location

Alcohols 1- Ethanol

Alcohols 2 - butanol

Ethers Contain a single bonded oxygen sandwiched between 2 carbon chains. *In the formula look for R 1 -O-R 2 * Naming - Name small chain, add “yl” and name large chain, add “yl” - Place chains in alphabetical order - Add ether

Ethers Butyl Ethyl Ether

Ethers Ethyl Methyl Ether

Aldehydes Contains a terminal double bonded oxygen In a formula, to identify an aldehyde look for R- CHO Naming -Name chain -Add “al” suffix -No number needed, always at the end.

Aldehydes Ethanal

Aldehydes Butanal

Ketones Functional Group: double bonded oxygen in the middle of the carbon chain In a formula, identify an ketone by looking for a R 1 – CO – R 2 Naming - Name chain -Add “one” suffix -Include number to indicate position Double bonded Oxygen

Ketones 2-pentanone

Organic Acids Functional group: COOH These are electrolytes because the H on the end dissociates, giving us an H + ion = Arrenhius acid. In a formula, identify an organic acid by looking for a R – COOH

Organic Acids Naming: -Name the parent chain -Add “oic acid” suffix -No number necessary.

Organic Acids Ethanoic acid

Organic Acids 3-methyl pentanoic acid

Esters Functional Group: In a formula look for R 1 -COO-R 2 1. Name chain bonded to single bonded oxygen first and add “yl” 2. Name chain bonded to double bonded oxygen 3. Add the “oate” suffix

Esters Ethyl pentanoate

Amines Functional Group: NH 2 located anywhere on chain. In a formula look for R-NH 2 Naming: - Name Chain - Add “amine” suffix - Use number to indicate location

Amines 1-butanamine

Amides Functional Group: terminal C=O and NH 2 In a formula look for R-CONH 2 Naming: - Name Chain - Add “amide” suffix - No number, always at the end.

Amides propanamide

What do you need to be able to do? Recognize what family a molecule belongs to based on functional groups and structure Be able to name simple examples from each family (except amino acids) Be able to draw simple examples from each family

These reactions are very good flashcard material, as it is important to able to recognize their general template to identify them. The acronym FSCAPES can be used to remember them. We will look at each of them individually.

Substitution Saturated hydrocarbons (alkanes only) under substitution reactions to attach other atoms onto the main chain. Must swap one atom with another, will have two final products. + Cl 2 + HCl + H 2

Substitution C 3 H 8 + Cl 2  C 4 H 10 + HBr  C 3 H 7 Cl + HCl C 4 H 9 Br + H 2

Addition Unsaturated hydrocarbons (alkenes/alkynes) The double or triple bond is broken, to make room to add an atom. No swap is needed. One final product.

Addition + Br 2 

C 3 H 6 + Cl 2  C 3 H 6 Cl 2 C 4 H 8 + HBr  C 4 H 9 Br

Combustion Organic compounds, mainly hydrocarbons are burned (react with O 2 ) to produce H 2 O and CO 2. To Identify: Hydrocarbon + O 2 Highly exothermic reactions, -  H, and are the first six reactions on Table I.

Fermentation The fermentation of glucose or fructose (carbohydrate) will produce ethanol and carbon dioxide as a product. To identify: look for alcohol (R-OH) and CO 2 as products. Glucose  2CH 3 CH 2 OH + 2CO 2

Esterification ALCOHOL + ORGANIC ACID  ESTER + WATER

+ ACID ALCOHOL ESTER + WATER Ethanoic Acid1-butanol Butyl Ethanoate

Saponification Reaction of a fat with a strong base like NaOH. The product is always glycerol and the salt of the acid (soap). General Formula: FAT + STRONG BASE  GLYCEROL + SOAP

Polymerization Joining small hydrocarbons called monomers together to form large hydrocarbons called polymers. Natural Polymers: Cellulose, Starch, Proteins Synthetic Polymers: Plastic, Nylon, Polyester

Condensation Polymerization Requires 2 dihydroxy alcohols monomers. They are joined together by removing water and hooked together with an ether (sandwiched oxygen) link.

Addition Polymerization Addition polymerization occurs with alkenes, the double bond on alkene monomer is broken and opened up. This allows the monomers to become single bonded to one another. The name “poly” is put in front of whatever monomer we are joining together. Identify by looking for “n” which represents the large number of monomer that is joined together.

Addition Polymerization nC 2 H 2  (C 2 H 2 ) n

Combustion Substitution Fermentation Addition Esterification Condensation Polymerization Addition Polymerization

Match the following reactions to the correct name: a) (C 17 H 35 COOCH) 3 H 2 + 3NaOH  3C 17 H 35 COONa + CH 2 OHCH 2 OHCH 2 OH b) CH 3 OH + CH 3 COOH  CH 3 COOCH 3 + H 2 O c) CH 4 + Cl 2  CH 3 Cl + HCl d) CH 4 + 2O 2  CO 2 + 2H 2 O e) C 2 H 4 + Cl 2  CH 2 ClCH 2 Cl f) C 6 H 12 O 6 2C 2 H 5 OH + 2CO 2 g) zymase Addition Polymerization Fermentation Substitution Combustion Saponification Esterification Saponification Esterification Substitution Combustion Addition Fermentation Polymerization