Chem 14D Flashcards
Hydroboration

Hydroboration:
Anti-Markovnikoff
syn addition

Oxymercuration

Oxymercuration:
Markovnikoff
syn + anti

Acid-catalyzed addition of H20 (hydration)

Acid-catalyzed addition of H20 (hydration):
Markovnikoff
syn + anti

Halogenation (Addition of HX)
HCl

Halogenation (Addition of HX):
Markovnikoff
syn + anti

Halogenation (Addition of HX)
HBr

Halogenation (Addition of HX):
Markovnikoff
syn + anti

Bromination (top reaction)

Bromination:
(Not Mark or Anti-Mark)
anti-addition

Halohydrin Formation (bottom reaction)

Halohydrin Formation (bottom reaction):
Markovnikoff
anti addition

Chlorination

Chlorination:
(not Mark. or anti-Mark.)
anti addition

Dihydroxilation
OsO4

Dihydroxialtion:
OsO4
(not Mark. or anti-Mark.)
syn addition

Dihydroxialtion:
KMnO4 (permanganate)

Dihydroxialtion:
KMnO4 (permanganate)
(not Mark. or anti-Mark.)
syn addition

Epoxidation

Epoxidation:
(not Mark. or anti-Mark)
syn addition

Hydrogenation

Hydrogenation:
(not Mark. or anti-Mark.)
syn addition

Radical addition of HBr

Radical addition of HBr:
Anti-Markovnikoff
syn + anti

Ozonolysis (Reductive workup, top reaction)
*bottom molecule can be S(Ch3)2 or Zn/H+

Ozonolysis (Reductive workup):

Ozonolysis (Oxidative workup, bottom reaction)
*can also use KMnO4 and acid

Ozonolysis (Oxidative workup):

Elimination of Hydrogen halides
*geminal dihalide

Elimination of Hydrogen halides

Elimination of Hydrogen halides
*vicinal dihalide

Elimination of Hydrogen halides

Hydrogenation (Addition Reactions fo Alkynes)

Hydrogenation (Addition Reactions fo Alkynes)

Partial Hydrogenation (Addition Reactions fo Alkynes)

Partial Hydrogenation (Addition Reactions fo Alkynes)

Addition of Hydrogen bromide (to form gem-dibromides)

Addition of Hydrogen bromide (to form gem-dibromides)
Markovnikoff

Addition of Hydrogen chloride (to form gem-dichlorides)

Addition of Hydrogen chloride (to form gem-dichlorides)
Markovnikoff

Bromination (Addition Reactions to Alkynes)

Bromination (Addition Reactions to Alkynes)
First addition is trans

Chlorination (Addition Reactions to Alkynes)

Chlorination (Addition Reactions to Alkynes)
First addition is trans

Deprotonation (Synthesis of Alkynes)
*Replace with Grignard: MgBr (molecule used in class)

Deprotonation (Synthesis of Alkynes)
*Replace with Grignard: MgBr (molecule used in class)
**Deprotonated alkyne makes excellent nucleophile

Good for making epoxides:
Percarboxylic acids
*Especially mCPBA (m-chloroperbenzoic acid)

Good for making diol:
Peracetic Acid with acidic H2O

True or False:
Warm, concentrated KMnO4 overoxidzes product and will not produce aldehydes, but instead carboxylic acids.
True
(Ex. diluted, basic, cold KMnO4 will produce vicinal diol from Z-alkene. Warm, concentrated KMnO4 will give carboxylic acid from Z-alkene)

Do internal alkynes have Markovnikoff or anti-Markovnikoff formations?
No, only terminal alkynes do.
Deprotonated terminal alkynes can do what type of reaction?
Sn2 (only 1°) - same reaction as a Grignard. Act as strong nucleophile.
True or False:
Grignards and Alkynes are incompatible.
True. Grignards will deprotonate Alkynes.
True or False:
H2 with a metal catalyst is a syn addition.
True.
True or False:
Hydrogenation of alkenes is a nonpolar process that requires a catalyst.
True
True or False:
Hydrogenation of alkenes generally proceeds via syn stereochemistry.
True.
True or False:
In very case of pericyclic reactions the products contain more σ (sigma) bonds and few pi bonds than the starting material.
True
True or False:
In pericyclic reactions stereochemical relationship in the starting materials are preserved through the reaction transition states and on into the products.
True
True or False:
The Dienophile has an electron withdrawing group which makes it relatiely electron-poor.
True
True or False:
The Diene has electron donating groups which makes it relatively electron-rich.
True
True or False:
Alkynes can act as Dienophiles as well.
True
Order from least to greatest in terms of electron-withdrawing strength:
CF3, Nitro Groups, Carbonyls (ketones, esters, aldehydes)
CF3 = Nitro Gropus (both strong) > Carbonyls (moderate)
*CF3 and Nitro have strong induction
Are Friedel-Crafts Alkylations or Acylations better reactions and why?
Friedel-Craft Acylations are preferred because they don’t have rearrangements (like Alkylations) and there’s a low chance of multiple acylations.
True or False:
Any carbocation can react with benzene.
True
Hydrohalogenation (Alkene)

Hydrohalogenation (Alkene):
Addition of HX
Markovnikov
Rearrangements

Hydration: Acid-catalyzed (Alkene)

Hydration: Acid-catalyzed (Alkene):
Markovnikov
Rearrangements
**lack of water gives dehydration - Elimination (E2, E1)

Halogenation (Alkene)

Halogenation:
Anti-addition
*Bridged halonium ion intermediate

Halohydrin (Alkene)

Halohydrin:
Anti-addition
Markovnikov for the –OH group
*Bridged halonium ion intermediate
(Attacked by water)

Hydration: Oxymercuration-demercuration (Alkene)

Hydration: Oxymercuration-demercuration (Alkene):
Markovnikov
No rearrangments

Hydroboration-oxidation (Alkene)

Hydroboration-oxidation (Alkene):
Syn addition
Anti-Markovnikov

Dihydroxilation - Vicinal Diol (Alkene)

Dihydroxilation - Vicinal Diol (Alkene)
Syn stereochemistry
(Oxidation to a glycol by OsO4)
*H2O2 or N-methylmorpholine N-oxide (NMO) can be used to reoxidize OsO4

Ozonolysis - Oxidative Cleavage (Alkene)

Ozonolysis - Oxidative Cleavage (Alkene)
*DMS or NaHCO3 can be used in step 2

Hydrogenation (Alkene)

Hydrogenation (Alkene):
Catalytic reduction
Addition of H2

Allylic Bromination (Alkene)

Allylic Bromination (Alkene):
*Radical intermediate

HBr addition to Alkene under radical conditions

HBr addition to Alkene under radical conditions:
Anti-Markovnikov
Radical

Oxidation of Alkenes by peroxycarboxylic acid

Acidity of terminal Alkyne

Acidity of terminal Alkyne:
*Strong bases like NaNH2, NaH, or lithium diisopropylamine (LDA)

Alkylation of acetylide anions.

Alkylation of acetylide anions.
Will displace halide from methyl or 1° haloalkane

Synthesis of an alkyne from an alkene

Synthesis of an alkyne from an alkene

Addition of Br2 or Cl2 (Alkyne)

Addition of Br2 or Cl2 (Alkyne)
Is anti slective

Addition of HBr (Alkyne)

Addition of HBr (Alkyne):
Markovnikov addition of one HBr, second HBr forms germinal dihaloalkane.

Keto-enol tautomerism (Alkyne)

Hydroboration-oxidation (Alkyne)
BH3

Hydroboration-oxidation (Alkyne)
BH3

Hydroboration-oxidation (Alkyne)
sia2

Hydroboration-oxidation (Alkyne)
sia2

Hydration: Acid-catalyzed (Alkyne)

Hydration: Acid-catalyzed (Alkyne)

Hydrogenation: Catalytic reduction (Alkyne)
Pd, Pt, or Ni

Hydrogenation: Catalytic reduction (Alkyne)
Pd, Pt, or Ni

Hydrogenation: Catalytic reduction (Alkyne)
Lindar’s Catalyst (cis)

Hydrogenation: Catalytic reduction (Alkyne)
Lindar’s Catalyst (cis)

Hydrogenation: Catalytic reduction (Alkyne)
2 Na, NH3 (trans)

Hydrogenation: Catalytic reduction (Alkyne)
2 Na, NH3 (trans)

Electrophilic addition to conjugated diene
HBr

Electrophilic addition to conjugated diene
HBr

Diels-Alder

Diels-Alder

Halogenation (Electrophilic Aromatic Substitution)
FeCl3 or AlCl3

Halogenation (Electrophilic Aromatic Substitution)
FeCl3 or AlCl3

Halogenation (Electrophilic Aromatic Substitution)
FeBr3 or AlBr3

Halogenation (Electrophilic Aromatic Substitution)
FeBr3 or AlBr3

Nitrogenation: NO2 (Electrophilic Aromatic Substitution)

Nitrogenation: NO2 (Electrophilic Aromatic Substitution)

Nitrogenation: NH2 (Electrophilic Aromatic Substitution)

Nitrogenation: NH2 (Electrophilic Aromatic Substitution)

Sulfonation (Electrophilic Aromatic Substitution)

Sulfonation (Electrophilic Aromatic Substitution)
*Process is reversible with H2O, heat, and catalytic H2SO4

Friedel-Crafts Alkylation (Electrophilic Aromatic Substitution)

Friedel-Crafts Alkylation (Electrophilic Aromatic Substitution)

Friedel-Crafts Acylation (Electrophilic Aromatic Substitution)

Friedel-Crafts Acylation (Electrophilic Aromatic Substitution)

(Electrophilic Aromatic Substitution)
Any Cation Intermediate

(Electrophilic Aromatic Substitution)
Anything that proceeds through cation intermediate can add to benzene ring.

Grignard (Carbonyls)

Grignard (Carbonyls)

Organolithium (Carbonyls)

Organolithium (Carbonyls)

Terminal Alkyne (Carbonyls)

Terminal Alkyne (Carbonyls)

Formation of Cynohydrin (Carbonyls)

Formation of Cynohydrin (Carbonyls)

Wittig Reaction (Carbonyls)

Wittig Reaction (Carbonyls)

Hydration (Carbonyls)

Hydration (Carbonyls)

Hemiactal Formation (Carbonyls)

Acetal Formation (Carbonyls)

Acetal Formation (Carbonyls)
*formed by dry acid. Reversible with aqueous acid.

Imine Formation (Carbonyls)

Imine Formation (Carbonyls)

Enamine Formation (Carbonyls)

Enamine Formation (Carbonyls)

Hydrazone (Carbonyls)

Hydrazone (Carbonyls)

Tollens Reagent (Carbonyls)

Tollens Reagent (Carbonyls)
*test for aldehyde, gives silver mirror

Selective Reduction (Carbonyls)
LiAlH4 or NaBH4

Selective Reduction (Carbonyls)
*both LiAlH4 and NaBH4 will do this reaction

Catalytic Reduction (Carbonyls)
Pt/H2

Catalytic Reduction (Carbonyls)
*will reduce other functionality

Reductive Amination (Carbonyls)

Reductive Amination (Carbonyls)

Clemmensen Reduction (Carbonyls)

Clemmensen Reduction (Carbonyls)

Wolff-Kishner Reduction (Carbonyls)

Wolff-Kishner Reduction (Carbonyls)
