University of Victoria CHEM 232
ORGANIC CHEMISTRY with BIOLOGICAL APPLICATIONS
Course website: web.uvic.ca/~chem232 (postings of course information,
midterm test dates and locations, course handouts, WileyPlus information,
important announcements, etc)
Pre-requisite: Chem 231 or equivalent (Chem 231 cannot be taken as a corequisite)
Passed Lab Credit: Must have taken Chem 232 (or 235) within last 3 years;
contact Dr. Peter Marrs (pmarrs@uvic.ca) to get credit for a passed lab.
Objectives: This course is the second half (Chem 231 is the first half) of a one
year introduction to organic chemistry. We will learn conjugation, aromaticity,
chemistry of aromatic compounds, aldehydes and ketones, carboxylic acids
and their derivatives, reactions of enols and enolates in organic synthesis,
amines, carbohydrates, and lipids. The laboratory component to Chem 232 will
teach basic laboratory techniques in organic chemistry drawn from material
learned in both Chem 231 and 232.
Website for online quizzes using WileyPlus:
Detailed information will be provided in class on how to access the
WileyPlus website.
© Peter Wan 2014
WileyPlus
1. Purchase of WileyPlus is required to access the online quizzes for this
course. We have negotiated a discounted package price that also includes
the e-text, e-solutions manual, and the lecture book.
2. There are 7 online quizzes that covers the major chapters of this course. It
is worth a total of 7% of your course mark. The quizzes can be written
anytime before the end of the last day of classes.
3. The online quizzes should be regarded as minimal preparation for this
course. You should also do the assigned problems, past midterms and
final exams, etc.
4. Plan ahead: no excuse will be accepted for failure to complete the quizzes
by the end of the term.
5. WileyPlus is also more than a place to do your quizzes. It has extensive
resources such as the e-text, video presentations, sample lectures, worked
out problems, etc. Check it out!
6. Your access code for WileyPlus is good for one academic year. You can use
the same code purchased for Chem 231 in September 2013.
Learning Organic Chemistry
1.
2.
3.
4.
5.
6.
It is not possible to learn every facet of organic chemistry but
key is know what you need to know.
Persistence, repetition, and practice are necessary. You may
not understand it the first time. Do the practice problems.
Some problems in organic chemistry have exact solutions;
others have more than one correct answer.
Organic chemistry is based on a relatively small number of
basic principles that must be mastered. The diversity of
structures and reactions also present a challenge.
The aim is to teach you to recognize, understand, manipulate,
and build organic compounds. DRAWING molecules in one
form or another is essential.
The 3D nature of molecules (STEREOCHEMISTRY)
present another challenging aspect of organic chemistry. A
molecular model set will help immensely.
Organic Chemistry can be conveniently
divided into four main subtopics:
1.
2.
3.
4.
Structures
Reactions
Mechanisms
Synthesis
There will be something in organic chemistry that
will interest you, if not now, then certainly later. Be
optimistic about this and you will find a reason to
engage yourself.
Representative Compounds Studied in Chem 232
Cyclopentadienyl
anion (cp-)
Diethyl Malonate
2,4,6-trinitrotoluene (TNT)
Mescaline
Valproic Acid
N,N-Diethyl-3methylbenzamide (DEET)
Estrone
D-Glucose
13.
CONJUGATED UNSATURATED SYSTEMS.
(approx. lecture time: 2 lectures)
Topics covered: 13.1-12.7, 13.9-13.10.
How to Spot Conjugated Systems: A conjugated system involves at least
one atom with a pz-orbital bonded (adjacent) to at least one p bond.
Cinnamaldehyde
responsible for the taste and
odour of cinnamon spice.
If you can draw at least one good resonance structure involving a double
bond and an adjacent atom (or atoms), it usually means it is conjugated
conjugated systems are very common and important in organic chemistry
The Importance of Conjugated Systems
Conjugated dienes (or conjugated polyenes) are
thermodynamically more stable than isomeric isolated alkenes.
This has major consequences in their structure and reactivity!
This is conjugated. It is
lower in energy than
two separate alkenes.
Graphene: The Ultimate Conjugated System
(The organic compound from pencils that seems to do everything)
1. One of the most exciting materials to be discovered since C60.
2. Geim and Novoselov received the Nobel Prize in Physics (2010)
for ground-breaking experiments with graphene.
3. One of the strongest materials known; 200 times stronger than
steel, with many possible uses including new mechanical materials
and in computer chips, etc.
A better picture of bonding in conjugated systems
requires Molecular Orbital (MO) Theory
According to this molecular
orbital, there is a p bond
between any two adjacent
atoms!
The Allyl System is the Simplest Conjugated System Possible
(The MOs shown below are the lowest energy ones)
The allyl system can be a radical, a cation, or a carbanion!
Reactions that generate conjugated systems are easier (faster)
compared to similar reactions that lack the conjugation
Which reaction will be the fastest?
But reactions of conjugated systems are more complex!
Principle of Kinetic vs Thermodynamic Control
Which pathway is for kinetic control?
Which is for thermodynamic control?
The Diels-Alder Reaction
Exo vs Endo Products
(It is easiest to see exo and endo products with the [2,2,1] system)
diastereomers
Thermodynamic product
(major product at high temp
when reaction is taken to
equilibrium)
Kinetic product
(product formed fastest
and is major product at
room or low
temperature)
Exo vs Endo Products
Exo
Endo
(The hardest part about the Diels-Alder
reaction is to be able to draw and
recognize exo and endo products)
Exo vs Endo Products
The Nobel Prize in Chemistry 1950
"for the discovery of the Diels-Alder reaction for making carbocyclic rings that
has immense utility in organic chemistry ”
Otto Diels
Kurt Alder
The dimerization of cyclopentadiene
via the Diels-Alder reaction