Presentation on theme: "REACTIONS OF ORGANIC COMPOUNDS Textbook: Chapter 2."— Presentation transcript:
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 ChangeReactants: Products Specific ChangeType of Reaction Example Change in C-C bonds 2:1Less multiple bonds/more H or functional groups around C Addition 1:2More 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 X 2 ) where X=Cl, Br, or I. – H and H (from H 2 ).
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, H 2 SO 4, 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 Aldehydes In the presence of oxidizing agent, aldehydes will become carboxylic acids. Oxidation of Ketone Like tertiary alcohols, ketones do not have a Hydrogen atom available to be removed. C-C bonds are too strong to be broken by an oxidizing 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.
PPs, pg. 78, #14-17 SR, 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, (every second one), 21. Unit 1 review: 1-16, 20, 21, 23, 28, 30-31, 32, 34, (every second one),