chapter 26 Flashcards
chapter 26: carbonyl compounds
what is an aldehyde functional group group
written as CHO H-C=0
what is a ketone functional group
written as CO C=O
How to turn aldehydes into carboxylic acids
add potassium dichromate and heat under reflux
Is the C=O bond polar
Yes it is polar as oxygen is more electronegative then carbon
what do C=O bonds tend to react with (electrophile or nucleophile )
They tend to react with nucleophiles they tend to “attack” the carbon atom
What does reacting an aldehyde with NaBH4 get you in an aqueous solution
you obtain an alcahol
Is NaBH4 acting as a reducing agent when reacting it with an aldehyde
yes
how can a reducing agent be represented
with the symbol [H]
how to produce a secondary alcahol from a ketone
Add NaBH4
What would be produced when a carbonyl compound reacts with HCN in the Prescence of H2SO4
A hydroxynitrile for example if H3CCH2CHO reacted with HCN then H3CCH2CHOHCN will be formed
mechanism for reacting NaBH4 with with a ketone or aldehyde
:H- attacks back of carbon
delta positive carbon
arrow from middle of = bond
to delta negative oxygen
draw arrow from lone pair on negative oxygen to delta positive hydrogen in water
draw arrow from middle of - bond to delta negative oxygen
delta positive hydrogen
will produce:
alcahol and OH negative
Mechanism for NaCN with a ketone or an aldehyde
:CN negative attacks back of delta positive carbon
arrow from middle of C=O bond to delta negative O
breaks double bond and makes it a single bond O:- forms
draw arrow from :O- to H+ should get a hydroxy nitrile
How to detect carbonyl compounds
Add 2,4 DNP (Bradys reagent) to a solution yellow orange precipitate forms
What is 2,4 DNP usually dissolved in to make it safe for use
sulfuric acid as friction could cause it to blow up
How to test between aldehyde and ketone
Add Tollens reagent a silver mirror will appear
Write the ionic equations for tollens reagent
Ag+(aq) + e- = Ag(s)
ketone + [O] = carboxylic acid
what ais the carboxyl group
mixture of carbonyl and hydroxyl (carboxylic acid )
Are carboxylic acids weak acids
yes
What is an acyl chloride
an acyl chloride has a C=O bond but there is also a chlorine on that carbon atom
How to name acyl chlorides
Take parent carboxylic and replace ending with -oyl chloride
what is an acid anhydride
an acid anhydride has 2 C=O bonds linked together with an oxygen atom and then 2 r groups on each carbon atom respectively
What does a carboxylic acid and an alcahol reacting together make
an ester and water
Name the products and reagents for for acid hydrolysis
ester heated with a dilute (aq) acid will create a carboxylic acid and an alcahol as H20 breaks down the ester
ester + H2O = alcahol + carboxylic acid
Name the products and reagents of alkaline hydrolysis
Irreversible
Ester goes to ethanoate ion(Na-O-C=O)
+ an alcohol
How to form ester from Acyl chloride
add acyl chloride with alcohol to form ester + HCL
How to form ester from Acyl chloride + phenol
add acyl chloride and a phenol to create a phenyl ester and HCl
why create an ester with phenol from an acyl chloride and not a carboxylic acid
A phenol is not reactive enough to form an ester with a carboxylic acid
Reactants and products of creating a carboxylic acid from an acyl chloride.
acyl chloride + water = carboxylic acid + HCl
How to make a primary amide from an acyl chloride reactants and products
acyl chloride + 2NH3(ammonia) = primary amide (sub OH with NH2 ) + NH4Cl
