10. Alcohol Reactions Flashcards
what does sodium borohydride react with and why?
aldehydes and ketones because it is a weak reducing agent
what does a reduction reaction lead to?
less bonds on an oxygen atom and more bonds on hydrogen
what does the reduction of aldehydes produce in terms of alcohol?
a primary alcohol
what does the reduction of ketones produce in terms of alcohol?
a secondary alcohol
what does the reduction of esters and carboxylic acids produce in terms of alcohol?
primary alcohol
what does lithium aluminum hydride react with and why?
carbonyls because it is a strong reducing agent
what does the reduction of amides produce?
amines
what type of solvent does lithium aluminum hydride react in and why?
because lithium aluminum hydride is more reactive than sodium borohydride the reaction is done at low temperatures and in non-protic solvents
decribe the reaction of esters to alcohols.
alcohol replaces where the lone single bonded oxygen is so you are left with a molecule with a hydroxyl (plus a hydroxyl and the rest of the chain that was cut off)
describe the reaction of amides to amines.
a carbonyl turns into two hydrogens
what chemical do aldehydes use to make themselves into primary alcohols?
PCC or pyridinium
is aldehydes to alcohol an oxidation or reduction reaction?
oxidation
what chemical do ketones use to make themselves into primary alcohols?
PCC (pyridinium), jones reagent and KMnO4 (potassium permanganate)
what are ketones subject to and why?
overoxidation because they lack the reactive hydrogen that aldehydes have
what chemical do carboxylic acids use to make themselves into aldehydes?
agents like Jones reagent or Tollens reagent
describe the reaction of making aldehydes from primary alcohols.
a hydroxyl groups turns into a carbonyl with a hydrogen beside it
describe the reaction of making ketones from secondary alcohols.
a hydroxyl groups in the middle of the carbon chain turns into a carbonyl
what is Jones reagent?
PCC
describe the reaction of making carboxylic acids from alcohols using the Jones reagent.
a carbonyl is added beside the hydroxyl group
describe the reaction of making a secondary alcohol into a ketones using the Jones reagent.
hydroxyl group turns into a carbonyl
describe the reaction of making carboxylic acids from aldehydes using the Tollens reagent.
a molecule with a carbonyl has a hydroxyl group added to the carbonyl
is tollens reagent weaker than jones reagent?
yes
what are the three main types of hydrogenation reactions?
- reduction of alkynes and alkenes to make alkanes using H2 and Pd/C
- reduction of alkynes to make cis alkenes using H2 and Lindlars catalyst
- reduction of alkynes to make trans alkenes using metal or liquid ammonia
describe a general hydrogenation reaction.
a double bond turns into two added hydrogens
what are the partial hydrogenation reactions?
- reduction of alkynes to make cis alkenes using H2 and Lindlars catalyst
- reduction of alkynes to make trans alkenes using metal or liquid ammonia
what is Tollens reagent?
a mixture of silver nitrate (AgNO₃), ammonia (NH₃), and sodium hydroxide (NaOH)
