Chapter 5 - Alcohol Flashcards
(22 cards)
How do you make a alcohol when the alcohol isn’t the highest priority ?
Hydroxy
What is a aromatic group with a hydroxyl group attached to it called ?
Phenol
What makes the hydroxyl hydrogen particularly acidic?
Resonance I’m the phenol ring
What are the three relative positions that must be indicated when a benzene contains two substituents ?
Ortho - adjacent carbon
Meta- two groups separated by one carbon
Para - two groups on opposite ends of a ring
How does increasing the hydroxyl groups in a compound affect the boiling and melting points ?
Boiling point and melting points increase significantly
How does hydrogen bonding occur ?
Hydrogen atoms are highly attracted to very electronegative atoms such as F,O and N
The slightly positive charge or the hydrogen attracts one of the slightly negative atoms to form a hydrogen bond
How does the presence of alkyl branches on aromatic alcohol affect the acidity of a molecule ?
Decrease acidity
What oxidant is used to to oxidize primary alcohols into anhydrides ? Why does the reaction stop after this conversion ? If another oxidant was used , aldehydes are hydrated to form what which are further oxidized into what ?
PCC
PCC lacks the water necessary to hydrate the aldehyde
Germinal diols ( 1,1-diols ), carboxylic acid
What can secondary alcohols be oxidized into and by what oxidant ?
Ketones , by PCC or any other oxidant
Can tertiary alcohols be oxidized ? Why ?
It is rare because they are as oxidized as possible and don’t have any H attached to the carbon group to which the hydroxyl group is attached to so that H group can’t participate in hydrogen binding
What are examples of oxidizing agents that are stronger than PCC ?
Chromium containing oxidizing agents such as sodium and potassium dichromate
What is the strongest oxidizing agent ?
CrO3 -chromium trioxide
What is Jones oxidation ?
Chromium trioxide is dissolved in acetone , and a primary alcohol is oxidized into a carboxylic acid , a secondary alcohol is oxidized to ketone
Since hydroxyl groups of alcohol make poor leaving groups what two compounds have been generated to cope with this ? What are their structures like ? What other function do they serve ?
Mesylate and tosylate because the make the hydroxyl group a stronger leaving group
Mesylate: - SO3 CH3
Tosylate : - SO3C6H4CH3
Mesyl and tosyl act as protective groups when you don’t want alcohol to react
How are aldehyde and ketals prevented from reacting ?
They are converted to acetal and ketal by reacting with alcohols which prevents them from reacting with strong reducing agents such as LiAlH4
What is the process called when acetal and ketal are returned to their reactive carbonyl form using an aqueous acid ?
Deprotection
How are quinone produced ?
Treat,end of phenol with oxidizing agent
What is the structure of quinone ?
6 carbon ring with double bonds on C2 and C5 and carbonyl groups on C1 and C4
How are hydroxyquinones formed ?
When quinones are further oxidized ; gain variable number of OH
What chemical properties allow ubiquinone to carry out its biological functions ?
Oxidation and reduction capacity
Long alkyl chain which allows it to be lipid soluble and act as a electron carrier within the phospholipid bilayer
Why do longer alkane chains with a hydorxyl group have a higher boiling point ?
Increase in van der waal forces
How does ubiquinone form ubiquinol?
Reduction
