CHM 123 INTRODUCTORY CHEMISTRY II           CHM 123 INTRODUCTORY CHEMISTRY II by SHITTU T.O. is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. CHM 123 INTRODUCTORY CHEMISTRY II 3 UNITS LECTURE BY: SHITTU T.O.

COURSE OUTLINE INTRODUCTION TO ORGANIC CHEMISTRY PURIFICATION AND ISOLATION OF ORGANIC COMPOUNDS QUALITATIVE AND QUANTITATIVE ELEMENTAL ANALYSIS VSEPR THEORY AND HYBRIDIZATION IN CARBON COMPOUNDS ORGANIC REACTIONS: TYPES, FACTORS AFFECTING REACTIONS, NUCLEOPHILES AND ELECTROPHILES CHEMISTRY OF HYDROCARBONS: ALKANES, ALKENES, ALKYNES AND PETROLEUM CHEMISTRY. ALKYLHALIDES CHEMISTRY OF AROMATIC COMPOUNDS. CHEMISTRY OF ALCOHOLS AND PHENOLS

COURSE OUTLINE CONT’D KETONES AND ALDEHYDES. CARBOXYLIC ACID AND DERIVATIVES. AMINES FATS AND OILS, CHEMISTRY OF SOAPS AND DETERGENTS. AMINO ACIDS AND PROTEINS. CHEMISTRY OF CARBOHYDRATES; POLYMERIZATION AND SYNTHETIC POLYMERS.

RECOMMENDED TEXTBOOKS Organic chemistry by L.G. Wade Organic Chemistry by Francis Carey Basic Organic Chemistry by Familoni Organic Chemistry by Paula Y. Bruice Organic Chemistry by Janice smith

Assessment Continuous Assessment (30%) includes: Attendance, term paper, assignment, presentation and/or mid-semester test Examination (70%)

Why students fail exams Failure can result from any of the following Perfectionism Unrealistic expectation Unpreparedness Ineffective study skills

LECTURE 1: INTRODUCTION TO ORGANIC CHEMISTRY Highlights Definition Of Organic Chemistry Occurrence/ Synthesis Of Organic compounds Applications Of Organic Chemistry Structure elucidation Representation Of Organic structures Molecular And Empirical formula Functional Groups, Homologous Series.

LEARNING OBJECTIVES At the end of this lecture, you should be able to: define organic chemistry and differentiate between organic and inorganic compounds represent organic structures using structural formula and line formula define functional groups and give examples of homologous series.

Organic chemistry It is a branch of chemistry that deals with the composition, uses and properties of carbon compounds (organic compounds). Organic compounds are carbon compounds that are not carbonates, diamond, graphite, oxides of carbon, sulphides organic compounds contain mainly carbon and hydrogen with few other elements like oxygen, halogens, nitrogen and metals.

Uniqueness of carbon There are numerous carbon compounds? Why??

There are large number of organic compounds because Carbon forms strong bonds to other carbon atoms and to a wide variety of other elements such as , C=O, C-S, C=N, C-Cl, C=C, C-C e.t.c. Carbon can self-link i.e it catenates to form chains and rings. These chains and rings can buid up to form variety of molecules.

Occurrence/synthesis of organic compounds

Occurrence of organic compounds Natural source: Organic compounds occur ubiquitously in plants and animals. Synthesis/ preparation: The first synthesis of organic compound was carried out in 1828 by a German Chemist, Friedrich Wohler. He synthesized urea from ammonium cyanate by heating it the absence of oxygen.

organic compounds from natural sources & applications

Organic compounds from natural sources chloroquine Natural rubber

Structure elucidation

Structure elucidation Techniques used in determining structures of organic compounds include: X-ray crystallography Infra-red spectroscopy Mass spectroscopy UV spectroscopy Nuclear magnetic resonance (NMR) spectroscopy

Representing organic structures Several kinds of formulas are used by organic chemists to represent organic compounds 1. structural formula: This formula shows bonding sequence in the molecule. i.e how an atom is linked to another. There are two types: Lewis structure and condensed structural formula

Examples: compounds Lewis structure Condensed structure ethane CH3CH3 N-hexane Isobutane (2-methylpropane) ethanol Diethylether

Exercise compounds Lewis structure Condensed structure methylamine acetonitrile ethanal Acetic acid (ethanoic acid)

2. line-angle formula or skeletal structure it is a shorthand method of representing organic structures. Examples : compound Condensed structure Line-angle formula N-hexane CH3CH2CH2CH2CH2CH3 Hex-2-ene Ethanol ethanal cyclohexane 2-bromobutane benzene

Exercise 1. Give the condensed formula of the following compounds: A B 2. draw the Lewis structure of the compound below: CH3COCH2CHCHCOOH.

Empirical and molecular formula An empirical formula shows the relative ratio in which elements are combined in a molecule. On the other hand, molecular formula shows the number of each element in one molecule of the compound. E.g the molecular formula of ethane is C2H6, While the empirical formula is CH3

Assignment Compute the empirical and molecular formula of each of the elemental analyses. In each case, propose at least one structure that fits the molecular formula: Hint: if an elemental analysis does not add up to 100%, the missing percentage is assumed to be oxygen C H N Molecular weight a. 40% 6.67% 90 b. 32% 18.7% 75

Functional groups and Homologous series. Functional groups is an atom or group of atoms that determines the physical and chemical properties of a molecule. Organic compounds are classified into different homologous series according to their functional groups. What is a homologous series??

A homologous series is a group of molecules in which successive members differ by a CH2 unit in the main chain. Compounds in a homologous series have the same functional group, but similar properties.

CnH2n+2 Homologous series General represenation Functional group examples General formula alkane R-H ……………. CH4, C2H6 CnH2n+2 alkenes C=C C2H4, C3H6 alkynes Benzene derivatives Ar-R, R can be H, alkyl phenyl group Alkylhalides R-X, X= halogens C-X Alcohol R-OH -OH Phenols Ar-OH

Homologous series General representation Functional group Examples Carboxylic acid Or alkanoic acid COOH Ester COOR aldehyde CHO ketones amine R-NH2 -NH- Thiol R-S-H S-H sulphide R-S-R S-R Nitro compounds R-NO2 -NO2 amide Acid chloride -COCl

Exercise Penicillin G is a naturally occurring antibiotic. Circle and name the functional groups in its chemical structure given below:

References Organic Chemistry by L.G. wade           CHM 123 INTRODUCTORY CHEMISTRY II by SHITTU T.O. is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. References Organic Chemistry by L.G. wade Organic Chemistry by G.M Loudon

TOPIC 2 ISOLATION AND PURIFICATION OF ORGANIC COMPOUNDS