Organic Chemistry

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Organic Chemistry CHEM 3332
Dr. Albright Office 218 Fleming Office Hours MW
2-4 PM
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Organic Chemistry CHEM 3332
Text L. G. Wade Organic Chemistry Fourth Edition
Solutions Manual Molecular Models
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Organic Chemistry CHEM 3332
Exams Quizzes - UNANNOUNCED- 10 Hour Exams
- 3 exams - lowest dropped - 25 each (50
total) Final Exam - 40 - NOTE TIME
NO MAKE-UP EXAMS, QUIZZES, or FINAL
Persons taking this course who may be in need
of additional help under the ADA (Americans with
Disabilities Act) guidelines should contact the
instructor for consideration of the matter.
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Top Ten Secrets of Success in Organic Chemistry!
10. Work every day or two on it - study a little
at a time.
9. Read the text book.
8. Go to class. Go to the Help Session classes.
7. Use molecular models at the start - play with
them.
6. Work with a pencil - dont use a
highlighter a. make and use notecards 1.
reaction mechanisms 2. Synthesis b. take notes
- www.chem.uh.edu/courses and
www.prenhall.com/wade c. recopy notes from
book/lecture
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Top Ten Secrets of Success in Organic Chemistry!
5. Dont memorize (everything). a. learn
concepts/ principles b. learn generalizations
4. Work in groups.
3. Work problems.
2. Work more problems.
1. Work extra problems!!!
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What you learned (were supposed to) in Chem
3331!!
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A. Reaction Summary
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Mech (for keto to enol trans.)
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B. Concepts
Chapter 1

• octet rule - writing Lewis structures
• electronegativity trends
• formal charges - computing them
• resonance - drawing structures
• drawing condensed/line formulas
• Brønsted acidity/bascity - trends
• Lewis acidity/basicity

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Chapter 2
1. s versus p bonds 2. hybrids number
angle sp3 4 109.5
sp2 3 120 sp
2 180 3. stereoisomers a.
constitutional isomers b. geometric isomers 4.
intermolecular forces 5. functional groups and
names
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Chapter 3

• 1. Structure of alkanes - staggered, eclipsed,
  gauche,
• Newman diagrams
• 2. Structure of cycloalkanes
• cyclohexane - axial versus equatorial, ring flips
• mono and disubstituted cyclohexanes

Chapter 4

• 1. kinetics
• a. rate constants
• b. activation energies (DG, DH, DS)
• c. rate determining step
• 2. thermodynamics
• a. equilibrium constants
• b. energies (DG, DH, DS)
• c. endothermic/ exothermic

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• 3. linear free energy relationships
• reactivity versus selectivity
• the Hammond principle

• 4. mechanism of halogenation reactions
• a. initiation, propagation, termination events
• b. energetics - how to compute them from BDEs
• c. selectivity - reactivity

5. reactive intermediates a. carbocations,
carbanions, radicals b. stabilities - resonance,
inductive effects c. drawing resonance
structures, allyl, benzyl, etc. d. carbenes
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Chapter 5

• Definitions
• a. chiral/ achiral
• b. diastereomer/ enantiomer
• c. configuration/ conformation
• d. mirror plane/ center of inversion
• 2. Absolute configuration know
  Cahn-Ingold-Prelog rules
• a. determine priority of groups around chiral
  center
• b. determine R, S configuration
• 3. More than one center of chirality
• a. Fischer projections
• i) manipulations, ie inverting, flipping,
  rotating
• ii) determining R, S
• b. Diastereomers - resolution of enantiomers

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Chapter 6
1. Nucleophilic substitution a. mechanisms of
SN1 and SN2 b. rate laws and stereochemistry c
. variation of nucleophile, structure of R group,
solvent and leaving group, L on reaction
rates d. rearrangements in carbocations 2.
Elimination reactions a. mechanisms of E1, E2
and E1cB b. stereochemistry and rate laws c.
orientation - Saytzeff versus Hofmann d. effect
of base, leaving group and alkyl group 3.
Factors favoring substitution versus
elimination
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Chapter 7
1. Know how to calculate elements of
unsaturation. 2. What the p bond in olefins is
and does - relative stability. 3. Nomenclature
cis/trans and E/Z names
Chapter 8

• Markovnikov versus anti-Markovnikov addition
• Syn versus anti addition

Chapter 9
1. Acidity of terminal alkynes
Chapter 10
1. Property of alcohols - lone pairs acidic H
Chapter 11
1. Techniques in multistep synthesis - pp. 489
-492 2. How to figure out reaction mechanisms -
pp. 480 -484
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C. Proposing a Reaction Mechanism Read pp.
480 -484 five times - understand it!!

• Types of reactions addition substitution of
  reagent
• to organic substrate.
• a. Electrophilic - requires a strong acid - H,
  R, etc.
• b. Nucleophilic - requires a strong base - -OH,
  -OR, etc.
• c. Radical - not common - generally requires an
• intiator (ROOR, etc.) - chain reaction - final
  step
• yields product intermediate used in the
  initial step.
• 2. General Patterns (not for free radical).
• a. A strong nucleophile will react with a site
  on a
• molecule which is weakly acidic, e.g.

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b. A strong electrophile will react with a site
on a molecule which is weakly basic, e.g.
c. In general a strong acid cannot survive in a
strong base or vice versa. d. Look for
activators - making a stronger electrophile or
nucleophile, e.g.
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e. Look for steps that are exothermic, e.g.
3. General strategies a. Always conserve
charge!! See each step illustrated before b.
Look first at the product and then at
reactant(s). Decide what bonds are made in
product Decide what bonds are broken in
reactant(s) Determine where the reactant(s)
hot spots are
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c. Each step must be bimolecular or unimolecular,
e.g.
d. Do not use line formulas - draw all atoms in
the molecules
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D. Proposing a Multi-step Synthesis Read
pp. 489 -492 ten times - understand it!!
General Patterns 1. Always work backwards - I
know, I know this is hard 2. Look at product
- what bonds can be formed from C-C bond
forming reactions - mark them! 3. Pick the C-C
bond that leads to the two most even
pieces. 4. If one route leads to a deadend,
then look at what you have done for possible
alternatives. Finally start at 2 for your
second choice. 5. KNOW ALL FUNCTIONAL GROUP
INTERCONVERSIONS
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Figuring out molecular structures
E. Review of Mass Spectroscopy Gives molecular
weight / molecular formula From molecular
formula get degree of unsaturation
molecular formula CvHwOxNyClz
degree of unsaturation Z number of double
bonds number of rings
Z

• 0 CnH2n2 alkane
• 1 CnH2n alkene (or cycloalkane)
• 2 CnH2n-2 alkyne (or diene or bicycloalkane)

Z 1/2(2C 2 -H) where C of carbons H
of hydrogens count O atoms as
zero count N atoms as one- half of a
carbon atom for halogens count as H
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F. IR Spectroscopy
IR measures stretching and bending
vibrations in molecules There are three
regions to look at (for now)
bend
stretch
stretch
stretch
3500-2700 cm-1
2200cm-1
1800-1600cm-1
well see uses for aromatic compds later