|
Texts: 1. Carey, F.A.;
Sundberg, R.J. Advanced Organic Chemistry, Part B: Reactions and Synthesis,
4th Ed.; Plenum Publishers: New York, 2001.
2. Smith, M.B.; March, J. Advanced Organic Chemistry, 5th
Edition; John Wiley & Sons: New York, 2001.
Course
Objectives and Philosophy
As this is a
graduate class, it is assumed that everyone is in the class because
they are highly motivated to truly master all of the fundamentals
of organic chemistry by consolidating all of their previous coursework
in the area, learning a few new reactions and concepts, and applying
this knowledge in an integrated way to new chemical problems. It
is the prime objective of this class that students emerge from it
with several indispensable skills, including the ability to:
- recognize most
modern synthetic reagents and illustrate their common use(s) with
sample reactions of their devising.
-
read, comprehend, and summarize
articles in journals such as the Journal of Organic Chemistry, Synthesis,
Tetrahedron
Letters,
Organic Letters, etc.
-
understand and illustrate the
mechanisms for all reactions to which they are exposed.
-
locate accurate literature precedent
for any transformation they wish to suggest, and to cite it the correct
format.
-
design an original synthesis
for any molecule presented to them (within reason), complete with accurate,
appropriate literature references for all non-trivial steps.
Class
Structure & Comments on the Textbooks
The two
texts for this course were chosen for very specific reasons.
We will loosely follow the organizational format of Carey & Sundberg,
but we won't just take each chapter as it comes along. For
instance, we'll spend some time in Chapter One (Alkylation
of Nucleophilic Carbon Intermediates), since not only does it address
the formation and uses of enolate anions and their equivalents, but
the concepts of kinetic vs. thermodynamic control of certain reaction
parameters are introduced and applied. Conversely, Chapter
Four (Electrophilic Additions to Carbon-Carbon Multiple Bonds)
and Chapter 11 (Aromatic Substitution Reactions) will probably
merit only one class meeting each, as the material therein is covered
in undergraduate courses. As we go,
I will often use papers from the current literature to illustrate
a topic or concept we've just discussed. Occasionally, I'll
make a homework assignment out of something in the literature -
finding an article where a certain reaction type is utilized, writing
a short (<1 pg.) analysis of a reaction in a current paper
(e.g., why this reaction was used and not a common alternative,
explain a stereochemical result, etc.). Also, I'll suggest
certain end-of-chapter problems each time we begin a new chapter.
C&S
has great problems, and their solutions are all provided via
references to the primary literature. I suggest
that you read the text (C&S) carefully,
with a pad of paper nearby. The text is very readable, but
many structures/ mechanisms/ figures are interspersed throughout,
and jotting down any mechanisms or figures that aren't immediately
obvious to you is a great way to learn and conceptualize the
material.. The material is also very well referenced, and
you're encouraged to consult primary papers for material which is
challenging for you. The other
book (March) is much less readable, in the way that C&S is.
The first nine of its 19 chapters constitute Part One, which is an
introduction to the reactions covered in Part Two. Part One
covers topics like stereochemistry, reactive intermediates, mechanisms,
etc.; Part Two's chapters have very general names, like Aliphatic
Nucleophilic Substitution, Addition to Carbon-Hetero Multiple
Bonds, and the like. March is where you
go to find leading references to something, along with a terse,
accurate summary of the topic; the book is over 2,000 pages
containing 40,000 references to the primary literature.
I leave it completely up to you when and how often to consult this
amazing reference work. Grading
and Class Policies
There will be
three literature assignments;
their specific topics and due dates will be announced in class. For
the first two, you will be asked
to find an organic synthetic reaction (or several) in the very
recent literature that accurately illustrate(s) an important concept
being discussed in class; detailed handouts will be supplied for
each assignment that explain what is expected. You will then analyze
the literature example, comparing and contrasting it with other,
similar strategies for effecting the same transformation. These
projects will be worth 50 points each. For the third literature project, you will locate
a very recent (published in 2002) total synthesis of a complex
molecule (again, specifics will be provided at the time the assignment
is formally distributed). You will then find an earlier synthesis
of the exact same molecule that utilizes a completely different
synthetic approach. Your assignment will be to perform a comparative
analysis of the two methods, pointing out differences and similarities
in both synthetic tactics and strategies. In addition to the written
report, you will also deliver a 20-minute oral presentation to the
class, utilizing overhead transparencies or
PowerPoint7, in a seminar format. This final literature project is
worth 100 points. Three
one-hour exams (100 points each) will be evenly
spaced over the term; the dates are given below.
The exams will all be in
two parts: an
out-of-class portion and an in-class section; each will be worth
50 points. The out-of-class part will be distributed one
week prior to the in-class exam date and will be due at the start
of that class period. The in-class part will require about 50 minutes
to complete. If you are going to miss an hour exam (for an
extremely good, documented reason), be sure and let
me know ahead of time, or, at the latest, before the
graded exam is returned to the class. There is no provision for
making up an exam. Exam
Schedule
|
Exam Number |
Out of Class Part Distributed |
Out
of Class Part Due, In-Class Occurs
|
|
I
|
Sept.
23
|
Sept.
30
|
|
II
|
Oct.
21
|
Oct.
28
|
|
III
|
Nov.
15
|
Nov.
22
|
|
FINAL
|
MON.,
DEC 9
|
WED.,
DEC. 18 - 2:45pm
|
The final examination (200 points) will
also consist of two parts, and will be handled exactly like the
hour exams. You will have two weeks for the take-home part, in which
you will prepare a proposal for the total synthesis of a complex
molecule. The in-class portion will be comprehensive, covering all
topics discussed during the term. Thus, the total points available
for the course equal 700 (two literature assignments at 50 pts each;
one at 100 pts; three exams at 100 pts each; one final at 200
pts).
Grades will be assigned based on a
curve related to class performance; thus, individual literature
assignments and exams will not receive a letter grade. The curve
will be updated throughout the semester after every hour exam and
presented to the class when the graded exam is returned, but you
are encouraged to stop in my office at any time to see where you
stand. After the last hour exam, the curve for the semester will
be unequivocally set (i.e., will not be changed as a result
of class performance on the final). That way, you will know, several
weeks in advance, the exact score you will need on the final exam
to earn a given letter grade for the semester.
Academic
Integrity
As noted above,
all exams, including the final, feature an out-of-class section in
addition to the in-class portion. In formulating your answers to
the take-home section, you may use any
sources of information you can think of except another person;
this includes faculty and students. Anyone found to be
in violation of this injunction will, at the least,
receive a zero for the exam;
receiving an F for the
course is actually more likely, depending on
circumstances.
Regardless of the consequence, the
Judicial Board will definitely be
involved, and the incident will become a part of your permanent record. Please, DO NOT
violate this policy the consequences are most definitely not worth
it, and it defeats the whole purpose of the exercise. And
yes, this kind of academic misconduct can be easily proven.
Note: It is possible that this injunction against consulting
another person will be waived for the out-of-class portion of the
final exam. You will be advised, in class, of whether or not this
is the case when we get close to the end of the semester.
Literature
Citations
The correct citation of literature precedent
is a very important skill in any science. You will get considerable
practice in this class, so please pay close attention to the
guidelines presented. Incorrect citations will result in point
deductions, regardless of the assignment.
When citing a literature reference, do not plagiarize the article. You
should be able to explain, in your own words, the concepts/principles
the article covers. It is easier to detect scientific plagiarism
than you may think, and, of course, proving it is trivial once the
copied article is found. If you are discovered to have plagiarized
an article, including sentences or phrases from it, you will receive
a zero for the assignment.
Many assignments in this class, as well as
any proposals you may write in your own career, require literature
precedent for chemical transformations you are suggesting. When
citing literature reactions, you must provide not only the correct citation, but also the exact reaction from the paper being claimed as
precedent.
Lets suppose you want to ozonize a
tetrasubstituted double bond to form two ketone functionalities.
An appropriate, correctly presented citation follows. Note
the ACS style of citation, as well as the structure numbers from
the original article (the numbers help find the reaction in the
article, should I decide to look it up). 1. Mori, M.; Hori, M.; Sato, Y. J. Org. Chem.
1998, 63, 4832. |
|
It is best to try to find precedent reactions
that involve molecules structurally similar to your own. This is
particularly important to support proposed chemoselectivity (the
selective reaction of one functional group in the presence of others
that might logically be expected to also react under the
conditions). For instance, if
you are proposing the reduction of a double bond via catalytic
hydrogenation, and the molecule also contains a nitro group which
you are claiming is not reduced under the reaction conditions, your
precedent reaction should illustrate this selectivity on an alkene
that has a nitro group somewhere on the molecule that is not reduced.
In a sense, your precedent reaction is proving that the
selectivity you claim is, in fact, feasible. Without such support,
a reviewer (or professor!) is going to ask why you think that the
nitro group will not be reduced simultaneously with the alkene
bond.
|