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Study Union Final Exam Review Fall 2017Monday 12/4, 12:00 – 2:00pm, Cape Florida
Organic Chemistry II (CHM2211)
SI Leader: Ajay G.
I. Nomenclature Nomenclature of Carboxylic Acid Derivatives
Base name (IUPAC) Base Name (common)
Example Compound
IUPAC Name Common Name
Alkane alkane - CH3CH3 Ethane -
Carboxylic acid Alkane Alkanoic acid
Alkane Alkanic acid
CH3COOH Ethanoic acid Acetic acid
Acid halide Alkanoic acid Alkanoyl halide
Alkanic acid Alkanyl halide
Ethanoyl chloride Acetyl chloride
Acid anhydride Alkanoic acid alkanoic anhydride
Alkanic acid alkanic anhydride
Ethanoic anhydride
Acetic anhydride
Ester Alkanoic acid alkyl alkanoate
Alkanic acid alkyl alkanate
Methyl ethanoate
Methyl acetate
Amide Alkanoic acid alkanamide
Alkanic acid alkanamide
ethanamide acetamide
Nitrile Alkanoic acid alkanonitrile
Alkanic acid alkanonitrile
ethanonitrile acetonitrile
Suffixes for Common Functional Groups:
Number of Carbons IUPAC Common name1 Meth- Form-2 Eth- Acet-3 Prop- Propion- 4 But- Butyr- 5 Pent- Valer-
Alkenes: -ene Alkynes: -yne
Alcohols: -ol Amines: -amine
Aldehydes: -al Ketones: -one
Ethers: alkyl alkyl ether or alkoxy alkane
Steps for naming a compound (loose guideline) 1. Identify parent chain: longest carbon chain containing priority FG2. Identify and name substituents3. Number parent chain: giving lowest locants possible4. Arrange substituents alphabetically: ignoring “di, tri, etc” . exception= “iso”5. Indicate any stereochemistry
Practice Problems
1. What is the proper name for this compound?a. 5-bromo-2-nitrophenylb. 3-bromo-6-nitrophenolc. m-bromo-o-nitrophenold. 5-bromo-2-nitrophenol
2. What is the IUPAC name for this compound? a. N-(4-chlorophenyl)ethanamideb. P-chlorobenzylethanamidec. 4-chlorobenzamide d. N-(4-chlorobenzyl)ethanamide
3. Name the following compound:
(2R, 4E)-5-methyl-4-hepten-2-ol
4. Which of these molecules contains amide, ketone, ester, and ether functional groups? B
a.
b.
c.
d.
II. Structure, Hybridization, Resonance, and Aromaticity
Constitutional isomers have the same molecular formula but different connectivity
of atoms and _______________ (identical/different) physical properties
Hybridization is determined by the number of _______ (π/σ/σ+π) bonds and
number of lone pairs
An atom that is sp3 hybridized has tetrahedral geometry
An atom that is sp2 hybridized has planar geometry
An atom that is sp hybridized has linear geometry
Aromatic compounds contain a ring with fully conjugated p orbitals and (4n+2)
number of pi electrons
Practice Problems
5. Draw the Newman projection that represents the most stable conformation of (CH3)2CHCH(CH3)2
6. Identify the lowest energy Lewis structure for nitrogen oxide (formal charges not shown)
a. c.
b. d.
7. Which of the following structures have eight π electrons?
I. II. III.
a. I onlyb. II onlyc. III onlyd. I, II, and III
8. Which of these structures is/are aromatic?
I. II. III. IV.
a. I onlyb. I and II c. II and IIId. I, II, and III e. All of the above
9. In which of these Lewis structures would sulfur be assigned a formal charge of +2?
a. b. c. d.
10. For which carbocation can the most resonance forms be written to show the delocalization of the positive charge?
a. b. c. d.
11. What is the hybridization of the carbon atom in the following carbene?
a. sp3
b. sp2
c. spd. s
12. Which compound absorbs at the shortest wavelength (highest energy) in the UV spectrum? a. A c.
b. d.
III. Acids and Bases A Bronsted-Lowry acid is a proton donor, while a Bronsted-Lowry base is a proton
acceptor
A Lewis acid is an electron acceptor, while a Lewis base is an electron donor
Relative acidity can be analyzed by comparison of their conjugate bases. The
stronger acid will have a ____________ (more/less) stable conjugate base
The four factors to consider when comparing the stability of conjugate bases are:
Atom, resonance, induction, orbital
Practice Problems
13. Which of the following is the weakest base? a. c.
b. d.
14. Rank the following in order of decreasing acidity (most acidic to least)
I. CH3OH II. CH3OH2+ III. CH3NH2 IV. CH3NH3
+
a. III > I > IV > IIb. II > IV > I > III c. III > IV > I > II d. II > I > IV > III
15. Rank the following in order of increasing acidity
I. II. III. IV.
a. I < II< IV < III b. III < I < IV < II c. I < IV < III < II d. I < III < II < IV
16. Which sets of hydrogen atoms in the compound below will undergo deuterium exchange with CH3CH2OD in the presence of CH3CH2ONa?
IV. III. II. I.
a. II and III onlyb. I, II, and III c. II, III, and IV, only d. I and IV only
17. Rank the following compounds in order of increasing acidity (least acidic to most acidic)
I. II. III. IV.
ANS: II < IV < I < III
IV. Stereoisomerism Stereo isomers have the same connectivity of atoms and but different arrangement
in 3D space
Enantiomers are _nonsuperimposible mirror images________
and have _________________ (identical/different) physical properties and differ in
the was they rotate plane polarized light
Diastereomers are stereoisomers that are not enantiomers
When is a compound chiral?
*****When it is non superimposable on its mirror image **** (super important, a
molecule does NOT need to have an sp 3 hybridized carbon with four different
ligands to be chiral.)
Practice Problems
18. Which of the following has “S” configuration? a. c.
b. d.
19. What is the correct stereochemical description of the relationship between this pair of molecules?
a. Enantiomersb. Diasteriomersc. Identicald. Constitutional isomers
20. Which of the following is/are optically active?
I. II. III.
a. I onlyb. II onlyc. III onlyd. I and III onlye. I, II, and III
V. Substitution and Elimination Reactions Practice Problems
21. Which mechanism best represents the E2 reaction between 1-bromopropane and KOH?a. c.
b. B d.
22. Draw all possible products of dehydrohalogenation of the following compound with potassium hydroxide:
ANS:
23. Predict the major product when the following compoundis treated with hydrobromic acid:
a. c.
b. B d.
24. Which substrate is most reactive towards solvolysis? a. c.
b. B d .
25. Which of the following is most reactive towards nucleophilic acyl substitution? a. N-methylethanamideb. Ethanoic acid c. Ethanoic anhydrided. Sodium ethanoatee. Ethanoyl bromide
VI. Reactions and Synthesis Practice Problems
26. What type of reaction converts FAD to FADH2?
FAD FADH 2
a. Dihydrogenation b. Electrophilic aromatic substitution c. Oxidation d. Reduction
27. Which reagent will accomplish the conversion shown?
a. CH3CH2Lib. CH3CH2CuLic. CH3CH2MgBrd. (CH3CH2)2CuLi
28. Draw the major product formed when benzene is reacted with 1-chlorobutane and aluminum trichloride
ANS:
29. Which set of reagents would most likely convert toluene to the following compound:
a. Br2 with UV lightb. ClCH3 with AlCl3
c. Br2 with FeBr3
d. Br2 in CCl4
30. Draw the polymer produced from the following monomer: (CH3)2C=CH2
ANS:
n 31. What are the products of the reaction when the following compound is heated in a solution
sodium hydroxide and water?
ANS:
O
32. Which compound is the product of an aldol condensation? a. . c
b. d.
33. Draw the product formed when benzaldehyde and acetophenone are reacted in a solution of sodium hydroxide and water.
ANS:
34. Which of the following methods will produce 1-pentanol?
I.
II.
III.
IV.
A. I onlyB. II and IIIC. I and IV D. I, II, and IIIE. All of the above
35. Which of the following methods will produce cyclopentanol?
A. C.
B. B D.
36. What is a key intermediate in the following reaction?
A. A B. C. D.
37. Which of the following dienes cannot participate in a Diels-Alder reaction? a. c.
b. ANS d.
38. Predict the product when the following compound is treated with excess chromic acid:
a. X c.
b. S d.
39. Show the starting materials that can be used to prepare the following compound by a Diels-Alder reaction.
a. S
b. S
c.
d. ANS
40. Which of the following compounds is a product of the Dieckmann cyclization shown below?
a. . c.
b. .ans d.
41. Predict the product of the following reaction:
a. c.
b. d.
42. Predict the product of the following reaction: .
43. Predict the product when ethylene glycol reacts with acetaldehyde under dry conditions (removal of water) a. A c.
b. d.
44. Predict the product of the following reaction:
a. c.
b. d.
45. predict the product of the following reaction:
46. Predict the product of the following reaction
a. A c.
b. d
VII. Spectroscopy
Infared Spectroscopy
(smaller / larger) atoms give bonds that vibrate at (higher / lower) frequencies, thereby corresponding to a higher wavenumber.
(stronger / weaker) bonds will vibrate at higher frequencies, thereby giving rise to a (higher / lower) wavenumber.
Identify the regions in which the following absorption peaks appear: Triple bonds, double bonds, single bonds, and bonds to hydrogen.
Conjugated π bonds absorb at a (higher / lower) wavenumber than localized π bonds. Explain.(See section 15.3)
The intensity of a signal corresponds to the polarity (dipole moment) of a bond. The broad signals associated with alcohols and carboxylic acids are due to Hydrogen bonding.
Explain. (see section 15.5)
Mass Spectroscopy
Fragmentation of the molecular ion generates a radical and a carbocation The mass spectrometer detects the carbocation fragment The molecular ion peak corresponds to the molecular weight of the compound The base peak is the tallest peak in the spectrum and corresponds to the (most / least)
abundant, or (most / least) stable, carbocation fragment. The base peak is (always / sometimes / never) the same as the molecular ion peak.
NMR Spectroscopy
If the replacement test yields the same compound, then the two hydrogen atoms are said to be homotopic and (are / are not) chemically equivalent.
If the replacement test yields enantiomers, then the two hydrogen atoms are said to be enantiotopic and (are / are not) chemically equivalent.
If the replacement test yields diastereomers, then the two hydrogen atoms are said to be diastereotopic and (are / are not) chemically equivalent.
The left side of an NMR spectra is described as downfield, and the right side of the spectra is described as upfield.
Bonds to H
Triple Bonds Double Bonds
Single Bonds
The more desheilded a proton is, the farther (upfield / downfield) it will appear in an HNMR spectra.
Practice Problems
47. Which compound would you expect to show a (M-18) peak in its mass spectrum?A. 2-methylbutane B. 1-butanol C. butanamine D. diethyl ether
48. Which of the following compounds would yield a molecular ion peak with an odd number m/z value? a. C9H15Fb. C7H10N2Oc. C8H10NId. All of the above
49. How many signal would you expect to see in the HNMR spectrum of (S) 2-bromopentane?A. 5B. 6C. 7D. 8E. None of the above
50. Which, if any, of the following will display spin-spin splitting in HNMR? a. (CH3)3COCH3
b. Br(CH2)3Brc. Para-xylene, CH3C6H4CH3
d. None of the above
51. Which of the following compounds would have a base peak at m/z=43? a. CH3CH2CH2CH2CH2CH3
b. (CH3CH2)2CHCH3
c. (CH3)3CCH2CH3
d. (CH3)2CHCH(CH3)2
52. The hydrogens shown areA. HomotopicB. Enantiotopic C. DiastereotopicD. Stereotopic
53. The hydrogens shown areA. Homotopic B. DiastereotopicC. Enantiotopic D. None of the above
54. A compound shows strong infrared absorption at 1100 cm-1, but none from 3300 to 3400 cm-1. Its 1H NMR spectrum has sharp singlet peaks at δ 1.3 and 4.0 ppm (intensity 3:2). Its proton decouples 13C NMR spectrum shows three peaks at δ20, 68, and 98 ppm. What is the structure of the compound?
a. A b. c. d.
Best of luck to you on all of your finals!!