Exam III-Short Answer Multiple Type Questions Flashcards
(95 cards)
1
Q
What is the hybridization state of the carbon attached to the alcoholic OH group?
A
SP3
2
Q
What is the hybridization state of the oxygen in the alcoholic OH group?
A
SP3
3
Q
2-pentanol is a … alcohol.
A
secondary
4
Q
- The IUPAC name of allyl alcohol is……………
A
3-propenol
5
Q
- The IUPAC name of n-amyl alcohol is…………….
A
1-pentanol
6
Q
- Alcohols form ………………. ion in the presence of a strong acid.
A
oxonium ions
7
Q
- The order of reactivity of alcohols with alkali metals is………………….
A
primary > secondary> tertiary
8
Q
- The oxidation state of carbon in methanol………………………………
A
-2 (-4 +2 = -2)
9
Q
- K2Cr2O7/H2SO4 is used for ………………………. reaction.
A
oxidation
10
Q
- Primary alcohols oxidize to form …………., which then oxidize to form …………………….
A
aldehydes; carboxylic
11
Q
- Secondary alcohols oxidize to form …………………….
A
ketones
12
Q
- Pyridinium chlorochromate (PCC) is used for …………………of alcohols to the corresponding……….
A
oxidation; aldehyde
13
Q
- A protonated alcohol is called ………………………
A
oxonium ion
14
Q
- Na2Cr2O7/acetic acid is used for ………………………. reaction.
A
oxidation (secondary alcohols)
15
Q
- Ethyl alcohol on chromic acid oxidation produces………………………
A
green color due to chromium (III) oxide formation / aldehyde
16
Q
- In the “alcohol breath analyzer test,” the chemical used is……………
A
ethanol or
potassium dichromate
17
Q
- Ethanol is oxidized in the liver to produce…………………
A
ethanal
18
Q
- The common name of picric acid is…………………….
A
trinitrophenol (TNP) or 2,4,6 - trinitrophenol
19
Q
- The active irritants in poison ivy and poison oak are………………….
A
urushiols
20
Q
- The phenolic compound which is used as an acid-base indicator is…………………………….
A
phenaphthalein
21
Q
- The toxicity of phenols to micro-organisms makes them excellent ………….
A
antiseptics
22
Q
- The compound 4-hexylresorcinol is used as an……………………….
A
antiseptic
23
Q
- Alcohols and phenols are weak……………………acids.
A
bronsted
24
Q
- Methanol is more acidic than ethanol—why?
A
- alkyl groups make an alcohol a weaker acid
- since ethanol has a longer alkyl chain than methanol, ethanol is a weaker acid
- methanol is therefore more acidic
25
35. Electron-withdrawing groups (EWGs) make an alcohol a stronger …………… by stabilizing the ……………………. base.
acid; conjugate base
26
36. Alcohols are weak acids and require a strong base to form the corresponding …………….
alkoxides
27
37. An electron-withdrawing substituent makes a phenol more …… by ………………. the negative charge.
acidic; delocalizing
28
38. Reduction of ……………………. gives primary alcohols, whereas reduction of ketones gives ………………… alcohols.
aldehydes; secondary
29
Lithium aluminum hydride (LiAlH4) is a more powerful reducing agent than ……………………. but less specific, and very
reactive with ……………
sodium borohydride (NaBH4); water
30
40. Which reducing agent would you prefer to reduce carboxylic acids to primary alcohol?
LiAH4 (lithium aluminum hydride)
31
Treatment of secondary and tertiary alcohols with phosphorus oxychloride in pyridine at low temperature
follows………………. route.
EZ elimination reaction
32
42. If 1° and 2° alcohols are treated with SOCl2 or PBr3 the reaction follows ……………….mechanism.
SN2
33
46. Alkyl tosylates react like alkyl ………….
halides
34
47. The SN2 reaction of an alcohol via an alkyl ……………… proceeds with ………. inversion.
halide; secondary
35
48. Grignard reagents react with …………… compounds to yield……………...
carbonyl; alcohols
36
49. An ether solvent is essential for the formation of a …………….
Grignard reagent
37
50. The non-bonded electrons from an ether help to …………..a Grignard reagent.
stabilize
38
The first part of the Grignard reaction is the formation of the Grignard reagent. This mechanism involves
a…………………reaction.
radical-transfer
39
52. Grignard reagents act as……………….. in adding to a carbonyl group.
nucleophilic carbon anions (carbanions)
40
54. Thiols are organic compounds that contain the ……….. group, also called……………….
-sulfhydryl group; mercaptans
41
55. Tetrahydrofuran (THF) is a solvent that is a ……………… ether.
cyclic
42
56. The IUPAC nomenclature of diethyl ether is…………………………
ethoxy ethane
43
57. The other name of epoxy-alkane is ………………………….
epoxide
44
58. An anticancer drug with oxirane moiety is ………………….
epothilone B
45
60. Ethers oxidize in air to form explosive ……………………. and ……………………….
hydroperoxides and peroxides
46
63. “Crown” ethers are useful as …………………. in nucleophilic substitution and other reactions
enhancers
47
65. The Williamson Ether Synthesis follows ……………………….route.
SN2
48
69. The anti-hypertensive B-Blocker drug (Propranolol) can be synthesized by exploring……………ring-opening methodology.
base-catalyzed epoxide
49
70. A naturally occurring polyether that interferes with Na+ ion transport across cell membranes is ………………………….
brevetoxin (neurotoxin)
50
71. The ………………. ring opening methodology is used to synthesize the bronchodilators salmeterol and albuterol.
unsymmetrical (attack w/nitrogen nucleophile)
51
72. What do you mean by host-guest complex? Indicate the ‘host’ and the ‘guest’.
- host-guest complex --> a crown ether-cation complex
-the crown ether is the 'host'
-the cation is the 'guest'
52
73. What is molecular recognition?
the ability of a host molecule (crown ether) to bind to specific guests (cations)
53
74. The ability of crown ethers to complex cations can be exploited in …………….
Nucleophilic substitution reactions
54
78. Oxirane is a synonym of
(i) oxygen
(ii) metal oxide
(iii) anhydrous alcohol
(iv) epoxide
(v) octane.
(iv) epoxide
55
How to name crown ethers:
of atoms - crown - # of oxgens
56
80. Intramolecular Williamson’s ether synthesis is an example of………………….reaction. ( e.g. SN1, SN2, E1, E2 etc.).
SN2
57
81. Nitrogen atom with a lone pair of electrons, making amines both ……………. and…………………….
basic and nucleophilic
58
84. Know the common names of heterocyclic amines as provided in the PPT.
- pyridine
- pyrrole
- quindine
-indole
- pyrimidine
- pyrrolidine
- piperidine
59
85. Amines with fewer than ……………………………. carbons are water-soluble.
5
60
86. Primary and secondary amines form …………………… bonds, increasing their boiling points
hydrogen
61
87. The nitrogen of an amine can behave as a……………………
nucleophile
62
88. Amines are stronger ……………………… than alcohols, ethers, or water.
bases
63
89. A phthalimide alkylation for preparing a primary amine from an alkyl halide is known as ………………………. synthesis.
Gabriel
64
Carboxylic acid derivatives can be converted into primary amines with loss of one carbon atom by both the
……………………. rearrangement and the ………………………… rearrangement.
Hofmann and Curtis
65
91. Alkyl azides are not nucleophilic, but they are ………………………
explosive
66
92. Why are arylamides instead of arylamines used for Friedel-Crafts Reactions of arylamines?
the amino group in arylamines forms a lewis acid-base complex with the AlCl3 catalyst, preventing further reaction. Therefore, the corresponding amide must be used
67
Azo-coupled products have extended conjugation that leads to low energy ……………. transitions that occur in visible
light (dyes).
electron
68
95. In amines, the nitrogen is ………………. hybridized.
SP3
69
In amides, the C=O group is strongly electron-withdrawing, making the nitrogen very
(a) weak base
(b) strong base
(c) weak acid
(d) strong acid (e) electron-rich
(a) weak base
70
Example of electron donating and electron withdarwing groups are:
(a) ⎯CH3, ⎯NH2
(b) ⎯OCH3 and ⎯CH3
(c) ⎯Cl,⎯NO2
(d) ⎯CN, ⎯CH3
(e) ⎯CH3, ⎯CN
e) -CH3, -CN
71
98. The product of Hofmann elimination is
(a) alkane
(b)alkyl halide
(c) acyl azide
(d) alkene
(e) isocyanate
(d) alkene
72
Primary arylamines react with nitrous acid (HNO2), yielding stable …………….. salts. This reaction is known as
…………………………reaction.
the sandmeyer
73
100. Base-promoted hydrolysis of an ester is called……………………………
saponification
74
Fischer esterification
Treatment of a carboxylic acid with an alcohol in the presence of an acid catalyst is known as………….
75
102. Nucleophilic acyl substitution is the characteristic reaction of …………………… derivatives.
carboxylic acid
76
103. Tetrahedral intermediate is formed in…………………….
Nucleophilic acyl substitution reactions
77
106. The carbon atom on the C(triple bond)N group is …. hybridized, making it linear with a bond angle of …...
SP; 180
78
107. Nucleophilic …….. substitution is the characteristic reaction of ………… derivatives.
acyl; carboxylic acid
79
The carbon atom on the C(triplebond)N group is SP hybridized, making it linear with a bond angle of ________
180
80
108. Why are two equivalents of ammonia required to prepare a primary amide from a carboxylic acid chloride?
One equivalent acts as the nucleophile to replace Cl, while the other reacts as a base with the HCl (byproduct)to form a quaternary ammonium salt. If the acid is not neutralized, the reaction becomes reversable.
81
Nucleophiles that are also strong …….. react with carboxylic acids by removing a ……. first, before any nucleophilic
substitution reaction can occur.
bases; proton
82
111. Treatment of a carboxylic acid with ………………….. affords an acid chloride.
thionyl chloride (SOCl2)
83
112. ……………. of a carboxylic acid occurs in the presence of acid but not in the presence of a base.
Esterification
84
113. Intramolecular esterification is known as ……………whereas intramolecular amidation is known as ………..
lactamasation; lactomasation
85
114. Dicyclohexylcarbodimide (DCC) is a …………….. .agent.
dehydrating
86
115. …………….. are the ………….most reactive of the carboxylic acid derivatives.
?
87
116. Nitriles are prepared by ……………. reactions of unhindered methyl and 1° alkyl halides with ¯CN.
SN2
88
117. The tautomeric form of amide is known as ………acid.
imidic
89
Know the rule to predict the major/minor products in the elimination reaction of alcohols.
"Saytzeff's rule".
90
Write a note on "Saytzeff's rule".
during intramolecular dehydration, if there is a choice of positions for the Carbon carbon double bond, the preferred location is the one that generally gives the more highly substituted alkene - that is, the alkene with the most alkyl groups attached to the double bonded carbons
91
The boiling point of ethanethiol (36 °C) is less than half of that of ethanol (78 °C) — Why?
Thiols boil at lower temperatures than alcohols because hydrogen bonds cant form between thiol molecules but can form between alcohol molecules. The more hydrogen bonds, the higher the boiling point
92
Arylamines and heterocyclic aromatic amines are considerably less basic than alkylamines — Justify. (3)
- The N lone pair electron in arlyamines is delocalized by interaction with the aromatic ring pi electron system
- it is therefore less able to accept H+ than alkylamines
-arylamines and heteroaromatic (heterocyclic aromatic) amines are considerably less basic than alkyamines (conjugate acid pKa = 5 or less)
93
Tertiary amines cannot form intermolecular H-bonds------Justify. (3)
- the structure of tertiary amines are R3-N
- all bonds made with Nitrogen are alkyl groups, so there are no hydrogens bonded to the nitrogen.
-With no hydrogens, H-bonding cannot occur.
94
Write a note on Curtius rearrangement.
carboxylic acid derivatives can be converted into primary amines w/ loss of one carbon atom by both the Hofmann rearrangement and the Curtius rearrangement
95
Arylamines are not useful for Friedel-Crafts reactions"—Why?
the amino group forms a lewis acid-base complex w/ the AlCl catalyst, preventing further reaction
