Chapter 8 Flashcards
Sigma bonds are _______ stable than pi bonds
more
In addition reactions, the double bonds acts as the _______ attacking the electrophilic species
nucleophile
_______ addition involves the pi e- attacking the + charge
electrophilic
_______ addition involves the Nuc- attacking the carbocation
nucleophile
In a regio_______ reaction: only one region attacked
specific
In a regio_______ reaction: major and minor products
selective
The addition of Hydrogen halides follows _______ rule: when adding H-X to db C, the H will add to the C with _______ H’s, leaving the X to the C with _______ H’s
markovnikov’s
more
less
For addition of hydrogen halides, stabilizing the _______ results in a faster reaction
C+ intermediate
Addition of Hydrogen halides results in _______ mixture if the product is chiral.
racemic
the addition of hydrogen halides also works for alkynes and may be performed twice by using _______ moles of H-X
2
add H to H rich side
_______ rule: when adding H-X to the db C, the H will add to the C with less H. In the presence of a peroxide!!!
anti-markovnikov
A db C may react with water in the presence of a strongly acidic catalyst (sulfuric and phosphoric acid) to form an alcohol. This reaction is known as _______
hydration
The goal of hydration is to add _______ “in place” of a double bond.
OH
What are the 3 types of hydration we learn in Ch. 8
1) regular (Markovnikov with Rearrangements)
2) oxymercuration-demercuration (Markovnikov with no rearrangements)
3) Hydroboration (anti-markovnikov with no rearrangements)
Oxymercuration-Demercuration leads to _______ of the H2O molecule to the Hg ring
anti-addition
When mercuration takes place in an alcohol solvent, the alcohol serves as the _______ to attack the mercurinium ion. This is known as _______ mercuration, which converts alkenes to ether
nucleophile
alkoxy
Hydroboration leads to _______ of the H and OH to a molecule
syn-addition
Hydroboration is a stereo_____ reaction
specific
a halogen molecule (______, ______, _______) is electrophilic; a nucleophile dbC can react with a halogen, displacing a halide ion
Cl2
Br2
I2
In addition of halogens (X2), solvents must be _______
inert
What are the 3 solvents that are inert for Halogen reactions
1) CH2Cl
2) CHCl3
3) CCl4
Addition of halogens (X2) leads to _______ of the halogen ion to the Halonium ion
anti-addition
Halogen addition is a stereo_______ reaction
specific
in all symmetric addition reactions, trans db + anti-addition results in __ product(s)
1
in all symmetric addition reactions, cis db + anti-addition results in __ product(s)
2
Bromine test: chemical test for the presence of _______
- brown=
- colorless=
unsaturation
no alkenes
alkenes
R-groups are _______, which stabalize the + or ẟ+
EDG’s
A halohydrin is an _______ with a _______ on the adjacent carbon
OH
Halogen
The solvent used in halohydrin formation has to be _______
polar protic
(H2O or ROH)
In halohydrin formation, the nucleophile (_____) attacks the more substituted, more electrophilic carbon atom
H2O
halohydrin formation leads to _______ of the H2O molecule to the carbon atom
anti-addition
Catalytic hydrogenation of an alkene is formally a _______, with H2 adding across the C=C to give an alkene
reduction
What are the required catalysts? (3)
1) Pd
2) Pt
3) Ni
Catalytic hydrogenation leads to _______ of the H and H to the double bond
Syn-addition
What are the 3 methods of adding methylene to alkenes?
1) diazomethane (CH2N2 with heat or UV)
2) simmons-smith (Cu alloy)
3) alpha elimination of haloform (CHX3 and strong base)
