sch 102 introduction to organic chemistry, …...sch 102 dr. solomon derese recommended text books...
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SCH 102
Dr. Solomon Derese
SCH 102Introduction to Organic Chemistry,
Chemistry of Alkanes and Cycloalkanes
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Recommended text books1. Organic Chemistry, John McMurry 2. Organic Chemistry, Francis Carry3. Organic Chemistry, Solomons T.W.G.
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Course EvaluationPRACTICALS (15 marks)Two CATS (15 MARKS)Final Exam (70 MARKS)
Dr. Solomon Derese; Chemistry Department Room 118; [email protected]
Teaching timetableMonday 8-10 am, MH1, AWednesday 8-10 am, MH1, B
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1. Introduction to Organic Chemistry.2. Atomic Structure, Chemical Bonding, Chemical
Structure and in Organic Compounds: Lewisstructure, resonance and hybridization.
3. Polar covalent bonds: electronegativity, dipolemoment
4. Overview of the Intramolecular and IntermolecularForces of attractions in Organic Molecules.
5. Overview of Types of Organic Reactions.6. Basic Concepts of Organic Reaction Mechanisms.7. Alkanes: Nomenclature, Structural Isomers,
Conformational Isomers and Reactions.8. Cycloalkanes: Nomenclature, Conformational
Analysis and Reactions.9. Overview of Stereochemistry.
Course Outline
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Success Depends on the Second
Letter
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Introduction to Organic Chemistry
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What is organic chemistry?
Organic chemistry is the study of the chemistry ofcarbon compounds.
The compounds of carbon are the centralsubstances of which all living things on this planetare made.Every living organism is made of organic chemicals.
The proteins that make up your hair, skin, andmuscles; the DNA that controls your geneticheritage; the foods that nourish you; and themedicines that heal you are all organic chemicals.
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DNA
RH
NH2
O
OHAminoacids
(The building blocks of proteins)
CH4
Methane (Chief constituent of natural gas)
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Examples of Organic Compounds
O
O
O
OH (Aspirin)Acetylsalicylic acid
(Pain reliever)
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DEET, the active ingredient in the most widely usedinsect repellents, is effective against mosquitoes,fleas, and ticks.
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Polyethylene
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Although carbon is the principal element in organiccompounds, most also contain hydrogen, and manycontain nitrogen, oxygen, phosphorous, sulfur,halogens or other compounds.
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Saflufenacil (Herbicide)
Example
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Anyone with a curiosity about lifeand living things, and anyone whowants to be a part of the remarkableadvances now occurring in medicineand the biological sciences, must firstunderstand organic chemistry.
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Although carbon is the principal element inorganic compounds, most also containhydrogen, and many contain nitrogen, oxygen,phosphorous, sulfur, halogens or othercompounds.
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Currently there are close to 37 million knownchemical compounds, of these 99% of themcontain carbon.
What makes carbon special?
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• As a group 4A element (at the centre of theperiodic table), carbon can share four valenceelectrons and form four strong covalent bonds.
• Furthermore, carbon atoms can bond to oneanother, forming long chains and rings fromthe simplest methane with one carbon complexmolecules such as DNA with more than 100million carbons.
The reason for this are:
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O
NH2
Each arrangement corresponds to a differentcompound, and has it own characteristic set ofphysical and chemical properties.
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Carbon atoms can attach themselves to one anotherto an extent not possible for atoms of any otherelements.
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Electronic configuration: 1s22s22p2
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Atomic number
Atomic mass
Carbon has four electrons in its outer most shell andrequires four more electrons in a covalent bond tohave a complete outer shell of electrons.
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1S 2S 2P2 2 2
Ground statepx py pz
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1. Carbon is tetravalent; that is it forms four bonds
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Bond formation in carbon
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2. A carbon atom can use one or more of itsvalence electrons to form bonds with othercarbon atoms.
Single bond
Double bond
Triple bond
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C C
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Functional Groups
• Chemists have learned through many years ofexperience that organic compounds can beclassified according to their structural featuresand that members of a given family often havesimilar physical and chemical behaviour.
• The structural features that make it possible forclassify organic compounds by reactivity arecalled functional groups.
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A functional group is part of a molecule where mostof its chemical reactions occur. It is the part thateffectively the compound’s chemical properties (andmost of its physical properties as well).
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The chemistry of every molecule, regardless of size and complexity, is
determined by the functional group it
contains.
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• They contain only C-C single bonds.• The alkanes are the simplest class of organic
molecules because they contain no functionalgroups. They are extremely unreactive.
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Alkanes
Cyclohexane3-MethylhexaneButane
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• Sometimes called olefins are hydrocarbonswhich contain C=C double bonds.
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Alkenes
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Alkynes are hydrocarbons that contain C≡C triplebond.
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Alkynes
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Compounds that contain benzene.
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Aromatic
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Alkyl Halides
Contain an alkyl group bonded to F, Cl, Br or I.
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Alcohols
Alcohols contain a hydroxyl (OH) group.
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Ethers contain R1–O–R2. It refers to any compoundthat has two alkyl groups linked through an oxygenatom.
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Ethers
R1-O-R2
O
Ethyl methyl ether
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Amines contain the amino (NR1R2R3) group, anitrogen attached to an alkyl group.
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Amines
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Alhdeydes and KetonesAldehydes (R–CHO) and ketones (R1–CO–R2) containthe carbonyl group C=O.
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Carboxylic AcidsCarboxylic acids (R–CO2H) contain the carboxyl groupCO2H.
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Esters (R1–CO2-R2) contain a carboxyl group with anextra alkyl group (-CO2R).
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Esters
R1 O
O
R2
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O
O
Methyl 3-methylbutanoate
O
O
Propyl propionate
O
O
Butyl acetate
O
O
3-Methylbutyl acetate
O
O
Methyl octanoate
O
O
Benzyl butanoate
Commercial applications of estersThe characteristics fruity smell of esters lead totheir use in artificial fruit essences.
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Amides (RCONR1R2)
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Amides
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Acid Chlorides
Acid chlorides (R–COCl)
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Cl
O
Cl
O
Acetyl chloride
3-Methylbutanoyl chloride
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Alkyl halideAromatic
Aromatic
Amide
Alkyl halide
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Application of Organic Chemistry in Drug Discovery – a Case of the Anticancer Drug
Imatinib
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IUPAC NameN-(4-Methyl-3-((4-(pyridin-3-yl)pyrimidin-2-yl)amino)phenyl)-
4-((4-methylpiperazin-1-yl)methyl)benzamide
Imatinib marketed as Gleevec/Glivec
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• Imatinib is used for the treatment of ChronicMyelogenous Leukemia (CML), before its discoverya diagnosis of a relatively uncommon cancer of theblood and bone marrow, was a death sentence.
43Dr. Brian Druker Dr. Nicholas Lydon
• Imatinib was discovered through collaboration of,an oncologist, Brian Drucker, and a biochemist,Nicholas Lydon, using results on the genetic basisof CML.
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Genetic Basis of CML
CML is caused by the mutated chromosome bcr-abl.
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A number organic compounds were screened fortheir ability to inhibit bcr–abl, and this resulted inthe discovery of imatinib as the drug of choice fortreatment of CML.
45Inhibition of bcr-abl by imatinib
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Overall survival on First-Line Imatinibtreatment of patients diagnosed with CML
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In this unit and subsequent organic chemistry unitsyou will learn about:
• Structure• Nomenclature• Properties• Reactions• Synthesis/Preparation
of such type of organic compounds.