Organic Chemistry 4 Flashcards
(182 cards)
1
Q
Define Hydrogenation
A
addition of H2 to a multiple bond
2
Q
Hydrogenation
A
alkene to alkane
3
Q
Notes on Hydrogenation
A
syn addition
4
Q
H2/Pd, Pt, or Ni
A
Hydrogenation
5
Q
How does heat affect stability?
A
less heat = more stable more heat = less stable
6
Q
Syn Addition
A
two atoms or groups add to the same face of a double bond
7
Q
Anti Addition
A
atoms or groups add to opposite faces of the double bond
8
Q
Stereoselectivity
A
a reaction in which a single starting material can give two or more stereoisomeric products but yields one of them in greater amounts than the other
9
Q
slowest to fastest rate of addition
A
HF«HI
10
Q
weakest acid to strongest acid HI, HF, HCL, HBR
A
HF«HI
11
Q
Markovnikov’s Rule
A
when an unsymmetrically substituted alkene reacts with a hydrogen halide, the hydrogen adds to the carbon that has the greater number o fhydrogesn, and the halogen adds to the carbon having fewer hydrogens
12
Q
Name the mechanism and any rule that applies: CH3CH2CH=CH2 + HBR CH3CH2CH(BR)CH3
A
Hydrohalogenation and markovnikov’s rule
13
Q
Define Hydrohalogenation
A
is the electrophilic addition of hydrohalic acids like hydrogen chloride or hydrogen bromide to alkenes to yield the corresponding haloalkanes
14
Q
Hydrohalogenation
A
Alkene to alkyl halide Alkyne to Alkenyl Halide Alkyne to Geminal dihalide
15
Q
Notes on Hydrohalogenation
A
Markovnikov’s Rule
16
Q
Hydrogen Halide ex: HBR, HCL
A
Hydrohalogenation
17
Q
Define Dehydration
A
loss of water
18
Q
Dehydration
A
alcohol to alkene
19
Q
What kind of mechanism does Dehydration take place
A
E1-carbocation E2-no carbocation
20
Q
H2SO4 or H3PO4
A
Dehydration
21
Q
Elimination 1
A
alcohol to alkene carbocation present H2SO4 or H3PO4 TERTIARY weak NU, weak base (NH3/CH3NH2/C5H5N or pyridine), heat SECONDARY heat, weak base, weak NU, good LG, steric hindrance
22
Q
Elimination 2
A
alcohol to alkene no carbocation H2SO4 or H3PO4 PRIMARY strong bulky base sterically hindered SECONDARY strong base sterically hindered secondary LG
23
Q
SN2
A
nucleophillic substitution chirality present=stereochem achiral present=no stereochem PRIMARY aprotic solvent,good NU,strong/weak base, unhindered SECONDARY aprotic solvent, good NU, unhindered, inversion, backside attack), no carbocation
24
Q
SN1
A
carbocation forms enantiomers TERTIARY protic solvent, good NU, forms enantiomers SECONDARY protic solvent, good NU,
25
Very Good NU
I, HS, RS
26
Good NU
Br, OH, RO, CN, N3
27
fair NU
NH3, Cl, F, RCO2
28
Weak NU
H20, ROH
29
Very Weak NU
RCO2H
30
Aprotic Solvents examples
no hydrogen bonding; no acidic hydrogen; stabilize ions; favor SN2 EXAMPLES DCM, THF, ethyl acetate, acetone, DMF, MeCN or acetonitrile, DMSN or dimethyl sulfoxide,
31
Protic Solvents examples
hydrogen bonding; acidic hydrogen; cations and anions;favor SN1 EXAMPLES Formic acid, n-Butanol, isopropanol, ethanol, methanol, acetic acid, water
32
Primary
SN2 E2
33
Tertiary
SN1 E1
34
Secondary
all four
35
alkyl halide/AgNO3/aq. EtOH
SN1
36
Alkyl Halide/NaI/acetone
SN2
37
Alcohol/HX
SN1
38
alcohol/SOCl2 or PX3
SN2
39
alkyl halide/H2O
E1
40
alkyl halide/KOH/heat
E2
41
alcohol/H2SO4/heat
E1
42
Dehydrohalogenation
alkyl halide to alkene
43
What kind of mechanism is Dehydrohalogenation
E2
44
Strong Base
Dehydrohalogenation of E2
45
Free Radical Addition of HBR
Alkene to Alkyl Bromide
46
Notes on Free Radical Addition
Anti-Mark peroxides needed
47
HBR, Peroxides
Free Radical Addition of HBR
48
Hydration
Alkene to alcohol Alkyne to ketone
49
Notes on Hydration
Markovnikov's
50
dilute H2SO4, H20
Hydration
51
Hydroboration-oxidation
Alkene to alcohol
52
Notes on Hydroboration-oxidation
Syn addition, anti-mark
53
1.B2H6, diglyme/2.H2O2, OH
Hydroboration-oxidation
54
Halogenation
Alkene to vicinal dihalide alkene to vicinal halohydrin alkyne to vicinal dihalide-trans alkene alkyne to tetrahalide
55
Notes on Halogenation
anti addition, OH adds to more substituted Carbon
56
X2, CHCL3, or CCl4
Halogenation
57
X2, H2O
Halogenation alkene to vicinal halohydrin
58
Epoxidation
Alkene to epoxide (carboxylic acid)
59
Notes on Epoxidation
Syn addition
60
peroxy acid
Epoxidation
61
Ozonolysis
Alkene to aldehydes or ketones alkyne to 2 carboxylic acids
62
Notes on Ozonolysis
Ozonide is intermediate
63
1. O3/ 2. H2O, Zn or (CH3)2S
Ozonolysis
64
Formation of alkyl tosylate
alcohol to alkyl tosylate
65
Notes on alkyl tosylate
-OTs is leaving group
66
Tosylate chloride
Alkyl Tosylate
67
Formation of Alkyne Anion
Terminal Alkyne to Alkyne anion (conj. base) Na, NH3
68
NaNH2, NH3
Alkyne Anion
69
Alkylation
Alkyne anion to alkyne
70
Notes on Alkylation
Alkyne anion is LG
71
Methyl or primary alkyl halide
Alkylation
72
Formation of Alkyne
Vicinal dihalide to alkyne
73
Notes of formation of alkyne
double dehydro-halogenation
74
1. 2NaNH2, NH3/ 2. H2O
Formation of alkyne
75
Hydrogenation of Alkynes
alkyne to alkane
76
2H2/Pt, Pd, or Ni
Hydrogenation of Alkynes alkyne to alkane
77
Lindlar Reduction
alkyne to cis alkene
78
Notes on Lindlar Reduction
Syn Addition
79
H2/CaCO3
Lindlar Reduction
80
Metal Ammonia Reduction
alkyne to trans alkene
81
Notes on Metal Ammonia Reduction
free radical intermediates
82
Na or Li/NH3
alkyne to trans alkene
83
X2
Alkyne to vicinal dihalide-trans alkene;halogenation
84
2X2
Alkyne to tetrahalide/halogenation
85
HX
alkyne to alkenyl halide;hydrohalogenation
86
2HX
Alkyne to geminal dihalide;hydrohalogenation
87
1. H20/ 2. H2SO4, HgSO4 (HgO)
alkyne to Ketone;hydration
88
1. O3/ 2. H2O
Alkyne to 2 Carboxylic Acids;ozonolysis
89
1* alcohol + Na2Cr2O7/H2SO4
aldehyde intermediate then to carboxylic acid
90
2* alcohol + Na2Cr2O7/H2SO4
ketone
91
1* alcohol + PCC (CrO3+pyridine+HCl)
aldehyde
92
chromic acid test
1* and 2* alcohol will react, 3* wont
93
Collins reagent
original PCC
94
Jones reagent
Dilute Chromic Acid in acetone
95
NaOCl/H2O
good oxidizer for acid sensitive compounds. Takes 1* all the way to a carboxylic acid
96
alcohol + KMnO4 in base or water
1* to carboxylic acids, 2* to ketones
97
HNO3/10-20*C
1* to carboxylic acids, 2* to ketones
98
alcohol + CuO +heat
oxidation, not good for lab synthesis due to high temps
99
alcohol + Cu-Zn/400*C
oxidation, not good for lab synthesis due to high temps
100
alcohol + DMSO + oxyalyl chloride then hindered base (like Et3N) and low temps (Swern Oxidation)
to aldehydes and ketones
101
alcohol + TsCl/pyridine
tosylate ester that can react via SN2
102
alcohol + H2SO4/heat
alkene (reduction), can then react to form an alkane catalytically
103
tosylate ester + LiAlH4
alkane
104
alcohol + HBr/H2O
R-Br
105
alcohol + NaBr, H2SO4
R-Br
106
Alcohol + (lucas reagent) HCl/H2O --ZnCl2--->
R-Cl
107
alcohol + PCl3
R-Cl + P(OH)3
108
alcohol + PBr3
R-Br + P(OH)3
109
alcohol + PCl5
R-Cl + POCl3 + HCl
110
R-OH + P + I
R-I + P(OH)3
111
R-OH + thionyl chloride (Cl2-S=O)--heat-->
chlorosulfite ester intermediate, then ion pair --> R-Cl + SO2 + HCl
112
Alcohol ---H2SO4, 180*C -->
E1 forms alkene
113
(2)1* alcohol ---H2SO4, 140*C -->
SN2 forms symmetrical dialkyl ethers
114
diol --H2SO4/100* -->
one less OH group, ,ethyl shift to where OH was, double bond to O. PINACOL REARRANGEMENT
115
alcohol + acid --H+ -->
ester + H2O
116
alcohol + acid chloride
ester + HCl
117
alcohol + sulfuric acid
alkyl sulfate ester, add another alcohol --> dialykl sulfate ester. really good leaving group
118
alcohol + nitric acid
alkyl nitrate ester
119
alcohol + phosphoric acid
phosphate ester
120
Williamson Ether Synthesis
1) form alkoxide with Na, K or NaH 2) Sn2 attack of alkoxide on alkyl halide
121
less hindered alkyl group (w/ halide or Ts) + more hindered alkoxide
williamson ether synthesis
122
more hindered alky; group (w/ halide or Ts) + less hindered alkoxide
elimination
123
R-X + Mg ---ether-->
R-Mg-X, grignard reagent
124
R-X + 2Li --->
R-Li(organolithium reagent) + Li+-X
125
Formaldehyde + R-MgX --1)ether solvent, 2) H3O+ --->
1* alcohol
126
Aldehyde + R-MgX --1)ether solvent, 2) H3O+ --->
2* alcohol
127
Ketone + R-MgX --1)ether solvent, 2) H3O+ --->
3* alcohol, 1 group added
128
acid chloride + 2R-MgX --1)ether solvent, 2) H3O+ --->
3* alcohol, 2 groups added
129
ester + 2R-MgX --1)ether solvent, 2) H3O+ --->
3* alcohol, 2 groups added
130
Ethylene Oxide + R-MgX --1)ether solvent, 2) H3O+ --->
1* alcohol, 2 carbons added
131
R-MgX + compound containing O-H, N-H, S-H, or terminal alkyne
protonated reagent + alkane
132
R-MgX + compound containing C=O, C=N, nitrile, S=O, N=O
will be attacked by reagent
133
1* alcohol + Na(s)
alkoxide
134
2* or 3* alcohol + K(s)
alkoxide
135
difficult alcohol + NaH in THF
alkoxide
136
Phenol + NaOH (aq) or KOH(aq)
phenoxide
137
Why doesnt a phenol need to be treated with Na or K metal to form a phenoxide?
Ion formation is favored due to resonance stabilization
138
aldehyde + 1)NaBH4, 2)H3O+
1* alcohol
139
ketone + 1)NaBH4, 2)H3O+
2* alcohol
140
carboxylic acid + 1)NaBH4, 2)H3O+
no reaction, NaBH4 is selective
141
ester + 1)NaBH4, 2)H3O+
no reaction, NaBH4 is selective
142
aldehyde + 1)LiAlH4, 2)H3O+
1* alcohol
143
ketone + 1)LiAlH4, 2)H3O+
2* alcohol
144
carboxylic acid + 1)LiAlH4, 2)H3O+
1* alcohol
145
ester + 1)LiAlH4, 2)H3O+
1* alcohol
146
alkene + 1)LiAlH4
no reaction
147
alkene + NaBH4
no reaction
148
aldehyde or ketone with double bonds + H2 --Raney Nickel-->
alcohol without double bonds
149
Na+-S-H + R-X
R-SH (thiol)
150
thiol + KMnO4 or HNO3
sulfonic acid (has 2 other resonance forms)
151
R2CuLi(gilman reagent) +R'-X
R'-R + R-Cu + LiX
152
2R-Li + CuI
R2CuI(gilman reagent formation) + LiI
153
secondary alcohol + Na2Cr2O7, H2SO4 -->
ketone
154
primary alcohol + Na2Cr2O7, H2SO4 -->
carboxylic acid
155
primary alcohol + PCC -->
aldehyde
156
alcohol + TsCl/pyridine, LiAlH4 -->
alkane
157
Alcohol + HCl or SOCl/pyridine -->
alkyl halide (R-Cl)
158
alcohol + HBr or PBr3 -->
alkyl halide (R-Br)
159
Alcohol + H2SO4 or H3PO4 -->
alkene
160
2R-OH + H+
R-O-R (ether)
161
alcohol + TsCl/pyridine -->
alkyl tosylate (R-O-Ts)
162
alcohol + acyl chliride -->
ester
163
alcohol + NaH -->
(alkoxide) R-O Na + H2
164
R-O + R'-X -->
ether (R-O-R') + X
165
Alcohol --> alkene (1)
acid-catalyzed dehydration of alcohol
166
Conversion of alcohols in alkyl halides (4)
1. alcohol + alkyl halide by substitution 2. convert an alcohol to a sulfonate ester for alkyl chloride 3. alcohol + SOCL2 4. alcohol + PBr3
167
Oxidation of alcohols
1a. primary alcohol + anhydrous chromium VI (aldehydes) 1b. primary alcohol + chromium VI (carboxylic acids) 2. secondary alcohol + chromium vi (ketones)
168
Synthesis of alcohols from alkenes
1. hydroboration-oxidation--follows Markovnikov's Rule 2. oxymercuration-reduction--anti-Markovnikov's Rule
169
Synthesis of Ethers and Sulfides
1. Williamson Ether Synthesis--alkylation of an alkoxide 2. Alkoxymercuration-Reduction 3. Alcohol dehydration to form ether 4. Alkene addition to form ether
170
Synthesis of Epoxides
1. Oxidation of Alkene with peroxycarboxylic acid 2. Cyclization of halohydrins (intra-molecular Williamson Ether Synthesis) 3.
171
Cleavage of Ethers
Using acid of either concentrated or trace amounts
172
Nucleophilic Substitution Reactions of Epoxides
1. Ring Opening under Basic--at least substituted carbon 2. Ring Opening Under Acidic--at most substituted carbon 3. Reaction with Grignard reagents to add alkyl groups
173
Preparation of Glycols
1. Acid-catalyzed reaction of epoxide with h20 2. Oxidation of alkene with OsO4 3. Reaction with KMnO4
174
Oxidative cleavage of glycol
using Periodic Acid
175
Nitration
HNO3 H2SO4
176
Sulfonation
SO3 H2SO4
177
Hydrogenation
H2 Ni
178
Oxidation
KMnO4 H20
179
Bromination
Br2 FeBr3
180
Chloronation
Cl2 AlCl3
181
Alkylation
CH3Cl AlCl3
182
Acylation
CH3COCl AlCl3
