9 Flashcards
Alcohol formula
R-O-H
Ether formula
R-O-R
Epoxide formula
three membered ring with an O in it
In an unsymmetrical ether the R groups are ______
different
an enol group is an sp2 hybridzied alcohol that is/isn’t attached to a ring
isn’t
A phenal is/is not attatched to a ring
is
In a ring -OH is labeled _
1
An epoxide is a special type of _____
ether
The C-O-C bon angle for an epoxide is __ degrees
60
Epoxides have ____ ______, making them more reactive than other ethers
angle strain
Alcohols and ethers have a _____ geometry
bent
In a carbon ring, the carbon bearing OH is labeled _
1
What does Isopropyl alcohol look like
Two alcohols changes the suffix to _____
diols
Compounds with three hydroxy groups are called ____
triols
If you had a methyl to the left of an ether and sec-butyl to the right of an ether, the ehter would be called:
Sec-butyl methyl ether
(b is earlier than m)
If you had an ethyl on both sides of an ether it would be called:
diethyl ether
In an either substituent (such as CH3O-) you replace the -yl with ____
-oxy
CH3O-
CH3CH2O-
(CH3)3C-O-
Methoxy
Ethoxy
Tert-butoxy
Name as an alekene oxide
2-methyl-1,2-epoxypropane
R-CH2-OH —->R3C-OH
To the right____
To the left_____
Increasing steric hinderence to the right
Increasing ability to hydrogen bond to the left
Alcohols, ether,s and epoxides having less than or equal to five C’s are H2O insoluable/soluable
while more means they H2O insoluable/soluable
soluable
insoluable
A crown ether acts as a host to a__
cation which is called the guest
Crown ethers can be used in ___ reactions
SN
Ethers can be easily prepared in ___ reactions
SN2
Alkooxides are formed through ____ chemistry
acid base
Epoxides can be synthesized from_____
halohydrins
-OH group of alcohols are a great/poor leaving group
poor
So -OH must be converted into a better leaving group for alcohol SN reactions.
R-OH+H-CL–>R-OH2+Cl-
Dehydration rections are the elimination of
H-O-H groups
Dehydrations are carried out by using ____ in the present of an _____ base
H2SO4
Amine
More substituated alcohols dehydrate slower/faster
faster (3 degree is best)
The more substituated alkene is the major/minor product when a mixture of cons isomers is possible
major
Reactions of Alcohol: Dehydration
Step 1
Step 2
Step 3
The O atom is protanated (-OH to -OH2) though sulferic acid
The C-O bond is broken forming a carbocation and H2O
Base romoves carbocations extra H in elimination
Reactions of Alcohols: dehrydration
E1 dehydration of 2 and 3 degree alcohols with acid gives clean elimination without ____ products
E1 dehydration of alcohols is more synthetically useful than E1 dehydrohalogenation of alkyl halides
SN1
Reactions of alcohols dehydration 1 degree*
Step 1
Step 2
The O atom is protonated with H2SO4
The C-H and C-O bonds are broken and the pie bond is formed
Alcohol dehydration is thermodynamically favorable/unfavorable
unfavorable (endothermic)
Despite being endorthermic, you can use ____ to remove product taking advantage of le chatliers principle
distillation
Unstable carbocations rearrange to more stable carbocations
The migrating group moves in a ___ shift
1,2
Movement of H is a 1,2-_____ shift
hydride
Movement of an alkyl group is a 1,2-____ shift
alkyl
A 1,2 methyl shift is a 4 step affiar
step 1 and 2
Step 3
Step 4
Formation of a 2 degree carbocation (-OH takes proton form H2SO4 then is eliminated as H2O)
Step 3 rearrangement of the carbocation by a 1,2-CH3 shift
Loss of proton to form the pie bond (picked off by HSO4-)
Reactions of Alcohols: Dehydration
Rearrangments may occur whenever a carbocation is formed as a reactive intermediate (and the carbon the H is moving to is less stable as to equalize stability)
absorb
Some alcohols ______ in the presence of strong acid
decompose
Acommon reagent for alcohol decomposition is ____ or ____
POCL3 or pyradine
Dehydration of alcohol (E2 elimination)
Steps 1 and 2
Step 3
Conversion of OH to a good leaving group (POCl3 attatches to OH and loses a Cl, then pyradine takes an H and O’s charge is restored)
The C-H and C-O bonds are broken and the pie bond is formed. The end leaving group is -OPOCl2 + a + charged pyradine
Conversion of alcohols to alkyl halides
Must use H-X archetype because -OH is a poor leaving group. The H forms H2O and R attatches to X
Proton transfer shit absorb
1 degree -OH have faster/slower rates of reactions with HX than 3 degree -OH
slower
Conversionof Alcohols to Alkyl Halides
