REACTIONS OF ORGANIC COMPOUNDS

Textbook: Chapter 2

Cancer and TAXOL

Read page 56 of your text and answer the following:

1. What is TAXOL? Where is it found?2. What was so exciting about the discovery of

the compound in the European yew?3. Explain why the study of organic chemistry is

really the study of functional groups.

The Main Types of Organic Reactions

• Addition• Substitution• Elimination• Oxidation• Reduction• Condensation• Hydrolysis

Addition

• Atoms are added to a double or triple bond– (decrease in multiple bonds)

• Two compounds usually react to form one major product.

Substitution

• Hydrogen atom or a functional group is replaced by a different functional group.

• Two compounds usually react to form two different products.

Elimination

• Atoms removed from a molecule to form a double bond.

• Reverse of addition.• More multiple bonds• One reactant usually breaks up to form two products.

Oxidation

• In organic chemistry, oxidation is a reaction in which a carbon atom forms more bonds to oxygen or less bonds to hydrogen. – (Increase C-O or decrease C-H).

Reduction

• Carbon atoms forms fewer bonds to oxygen, O, or more bonds to hydrogen, H. – Less C-O or C-C bond. (ex// C=O to C-O).

• Opposite of oxidation.

Condensation

• Two organic molecules combine to form a single organic molecule.

• Water is usually produced.

Hyrolysis

• Reverse of condensation• Water is added to a bond, splitting the organic

molecule into two.

Classifying Reactions

• Complete the following table. This is to help you identify different kinds of reactions easier!

General Change Reactants:Products

Specific Change Type of Reaction

Example

Change in C-C bonds

2:1 Less multiple bonds/more H or functional groups around C

Addition

1:2 More multiple bonds/less H or functional groups around C

Elimination

... ... ... ... ...

Identifying Reactions

• PP pg. 63

2.1 Homework

Page 63, # 1 b,c. #2 b, c. #3 b. #4 b.

SR, page 64, #1 - 5

2.2 Reactions of Functional Groups

Alkenes and Alkynes have ____________ or ________ bonds. Multiple bonds are more ____________ than single bonds.

• Alkenes and Alkynes undergo addition reactions involving:– H and OH (from water)– H and X (from XH) where X=Cl, Br, or I.– X and X (from X2) where X=Cl, Br, or I.

– H and H (from H2).

Symmetry of Reactants

• The product of an addition reaction depends on the symmetry of the reactants. – Symmetrical alkene: identical groups on either

side of double bond. E.g. Ethene:

– Asymmetrical. E.g. Propene.

• Added molecules can also be symmetrical/assymetrical.– Symmetrical: E.g. Chlorine.

– Asymetrical: E.g. Water.

What do you notice about these reactions?_______________________________________

__________________________________________________________________________

What do you notice about this reaction?_______________________________________

__________________________________________________________________________

Markovnikov’s Rule

• Used when the products are two isomers.• Determines which isomer will be most

prominent (only a small amount of other isomer will be produced).

• MARKOVNIKOV’s RULE: the halogen atom or OH group in an addition reaction is usually added to the carbon bonded to the most carbon atoms.

Determining the Product of a Reaction

PP, page 67.

Addition to Alkynes• Since alkynes have triple bonds, _________ addition reactions

can take place in a row. • If one mole of a reactant, such as HCl, Br2, or H2O is added to

one mole of an alkyne, the result is a substituted alkene.

• If two moles of the reactant are added to one mole of an alkyne, a second addition reaction takes place, producing an alkane.

Markovnikov’s Rule and Alkynes

Asymmetrical alkynes follow M.’s rule. when an asymmetrical molecule is added to the triple bond. Note: the halogen is bonded to the carbon around the triple bond that is bonded to the most carbons. The hydrogen is bonded to the carbon around the triple bond that has the most hydrogens. THE RICH GET RICHER!

Reactions of Aromatic Compounds• Benzene’s stable ring does not usually accept

the addition of other atoms. • Aromatic compounds undergo substitution.

• Addition reaction does not occur because the product of this reaction would be less stable than benzene.

Reactions of Alcohols• Substitution Reactions of Alcohols– When a Halogen acid, such as HCl, HBr, or HI,

reacts with an alcohol, the halogen atom is substituted for the OH group of alcohol.

– An alcohol is a product when an alkyl halide reacts with OH- in a basic solution.

• Elimination Reactions of Alcohols– When an alcohol is heated in the presence of a

strong acid and dehydrating agent, H2SO4, elimination reaction occurs.

• Oxidation of Alcohols- In the presence of an oxidizing agent, an alcohol is oxidized to form

an aldehyde or ketone. - A primary alcohol is oxidized to an aldehyde. If the aldehyde is oxidized further,

it becomes carboxylic acid.

- A secondary alcohol is oxidized to a ketone. (Can a further oxidation occur?)

- A tertiary alcohol cannot be oxidized.

PP pg. 73 #9-13.

Oxidation of Aldehydes and Ketones

• Aldehydes and ketones react differently with oxidizing and reducing agents.

Oxidation of AldehydesIn the presence of oxidizing agent, aldehydes will become carboxylic acids.

Oxidation of KetoneLike tertiary alcohols, ketones do not have a Hydrogen atom available to be removed.C-C bonds are too strong to be broken by anoxidizing agent.

Reduction of Aldehydes and Ketones• Aldehydes are reduced to produce primary alcohols.

• Ketones are reduced to produce secondary alcohols.

Reactions of Carboxylic Acids• Like other acids, carboxylic acid reacts with a base to produce a

salt and water.

• A carboxylic acid reacts with an alcohol to produce an ester. A strong acid (e.g. Sulfuric acid) catalyzes the reaction.

– ESTERIFICATION REACTION! SPECIAL CONDENSATION REACTION.

Reactions of Esters and Amides• Both undergo hydrolysis reactions. • Hydrolysis of an ester produces a carboxylic acid and an

alcohol. • The hydrolysis of an amide produces a carboxylic acid and

an amine. • Hydrolysis can be acidic or basic hydrolysis.

– In acidic: org. Mol. Reacts with water in the presence of an acid.– In basic: org. Mol. Reacts with OH- ion, from base or water in

the presence of a base.SOAP IS MADE BY THE BASIC HYDROLYSIS OF ESTER ONDS IN OILS

OR FATS.

Concept Organizer

PPs, pg. 78, #14-17SR, pg. 79, #1-8.

2.3 – Molecules on a Larger Scale: Polymers and Biomolecules

• For the most part, we have seen small organic molecules so far.

• Many of the organic molecules that are used industrially, such are plastics, are large organic molecules.

POLYMER: very long molecule made by linking together many smaller ‘building blocks.’

MONOMER: the ‘building blocks.’(PAPER CLIPS)

Synthetic Polymers

• Plastics: polymers that can be heated and moulded into specific shapes and forms. – Polyethene: plastic bags.

• Adhesives, rubber, chewing gum, and styrofoam.

Natural Polymers

• Glucose, _____________, is the monomer for the natural polymer _____________.

Fabrics

• Some polymers can be spun into long, thin fibres.

• Fibres woven into natural fabrics (cotton, linen, and wool) or synthetic fabrics (rayon, nylon, and polyester).

Names of Polymers

• Polymers are formed by either addition and condensation reactions.

• The name of a polymer is usually written with the prefix poly-. (polyethene).

• The common name of the monomer is often used rather than the IUPAC name. (the common name of ethene is ethylene. Therefore, polyethene is often called polyethylene).

Addition Polymerization

• Monomers with double bonds joined together through multiple addition reactions to form a polymer.

Examples of Addition Polymers

Condensation Polymerization

• Monomers are joined together by the formation of ester or amide bonds.

• Water is usually produced. • Each monomer must have two functional

groups. • Ester Bonded Polymers: polyesters. From

esterification or diacids and dialcohols.• Amide Bonded Polymers: nylons or polyamides.

PPs, pg. 84. #18-21

Natural Polymers

• Synthetic polymers have been made by imitating natural polymers.

• Biochemistry: study of organic compounds and reactions that occur in living things.

• Important natural polymers: _________________, __________________,

___________________, __________________.

Amino Acids and Proteins

Proteins: composed of monomers called _________________. Found in meat, milk, eggs, and legumes and make up wool, leather, and silk. Fingernails, hair, and skin are composed of different proteins.

Three functions of proteins within our bodies are: __________________________, _________________________, and ______________________________.

Amino Acids- 20 common amino acids all containing a carboxylic acid group and an amino group.

- each amino acid has a different side chain, which is attached to the center carbon atom.

• Amino acids –> Protein• Aas linked by amide

bonds to form polymer.• Shape and biological

function of protein depends on sequence of amino acids. – Insulin: more than 50

amino acid groups. – Infinite number of

proteins are possible. – DNA contains

blueprints for making specific proteins.

Carbohydrates

• Also called a ‘saccharide’ – contains either an aldehyde or ketone group with two or more hydroxyl groups.

• C=O group reacts with OH group within linear structure to form a ring in most cases (in monomer)

• Common monomers are glucose and fructose.• Carbs found in bread, pasta, potatoes and fruits. • Primary source of energy – used in cellular

respiration.

• Monosaccharide: simple carbohydrate, or simple sugar.

• Disaccharide: contains two monosaccharides.– -OH group on one monomer reacts with –OH group

on another monomer to form an ether –O- linkage: special kind of __________________.

• Polysaccharide: many saccharide units (monomers). – Glucose polysaccharides:– Cellulose: plant structural material.– Starch: plant energy storage material. – Glycogen: animal energy storage.

Nucleotides and Nucleic Acids

• Nucleic Acids: DNA and RNA– DNA – found mostly in nuclei of cells. – Each strand of DNA is a polymer composed of

repeating units called nucleotides. – One DNA strand may have more than one million

nucleotides. – RNA – works closely with DNA to produce

proteins.

Lipids

• Not polymers, but very large.• Not soluble in water, but are soluble in other non-

polar solvents. – Large hydrocarbon parts, therefore,

_________________________.– Fats, oils, waxes.

• Fats: one glycerol ester linked three long-chain carboxylic acids. Solid at room temp.

• Oils: same structure, but liquid at room temp.• Waxes: esters of long-chain alcohols and long-chain carboxylic

acids.

• Lipid function:– Long-term storage of energy.– One gram of fat contains 2.25 X more energy than one

gram of carb or protein.– If more carbohydrates are consumed than needed, body

converts excess to fat broked down when needed.– Cell membranes.– Hormones (cholesterol, testosterone). – Vitamins.– Insulation and packaging.

SR. Pg. 95. #1 – 5.

Homework

All PPs and SRs outlined in this Lecture.Read the section “Risks of the Polymer Industry”

on page 88 and make short notes.Read the Chemistry Bulletin on Page 89 and

make short notes. Answer questions 1-3.

THIS HAS BEEN UPDATED. REFER TO THE HANDOUT, ‘THE POLYMER INDUSTRY.’

Notice/Review (UPDATED)Organic Chemistry Unit Test on WEDNESDAY (April 27)Suggested Review:• Read over Intermolecular Forces section on page 23.

Use this knowledge to create a concept map outlining the Physical Properties of all functional groups we’ve looked at (in tables throughout ch. 1).

• Ch. 1 Review (pg. 52):– Know all key terms.– # 1, 3 – 14, 15-16, 21, 22.

• Ch. 2 Review (pg. 105)– Know all key terms.– # 1-11, 13-17, 18-20 (every second one), 21.

• Unit 1 review: 1-16, 20, 21, 23, 28, 30-31, 32, 34, 36-40 (every second one),