Aldehydes and Ketones Flashcards
Aldehydes and ketones
_________ AND _______ are the compounds which contain a
carbonyl functional group
Aldehydes and ketones
A carbon atom double-bonded to an oxygen atom
Carbonyl group
All carbonyl groups have a
trigonal planar structure
Carbonyl is attached to at least one H atom in _____
Aldehydes
Carbonyl is directly attached with two carbon atoms in _____
KETONES
carbonyl carbon atom bonded to an oxygen atom
Esters
carbonyl carbon atom bonded to a nitrogen atom
Amide
_______ are not possible but cyclic ketones are known
Cyclic aldehydes
ALDEHYDES - IUPAC RULES
Select as the parent carbon chain the longest carbon
chain that includes the carbon atom of the carbonyl group
rule 1
ALDEHYDES - IUPAC RULES
Name the parent chain by changing the -e ending of the
corresponding alkane name to -al.
rule 2
ALDEHYDES - IUPAC RULES
Determine the identity and location of any substituents,
and append this information to the front of the parent chain
name.
rule 4
ALDEHYDES - IUPAC RULES
Number the parent chain by assigning the number 1 to
the carbonyl carbon atom of the aldehyde group.
rule 3
KETONES - IUPAC RULES
Select as the parent carbon chain the longest carbon
chain that includes the carbon atom of the carbonyl group
rule 1
KETONES - IUPAC RULES
Name the parent chain by changing the “-e” ending of
the corresponding alkane name to “-one.”
rule 2
KETONES - IUPAC RULES
Number the carbon chain such that the carbonyl carbon
atom receives the lowest possible number
rule 3
KETONES - IUPAC RULES
Determine the identity and location of any substituents,
and append this information to the front of the parent chain
name.
rule 4
KETONES - IUPAC RULES
Cyclic ketones are named by assigning the number 1 to
the carbon atom of the carbonyl group
rule 5
Isomers between aldehydes and ketones are called
functional
group isomers
Two types of isomers:
Position of the functional group is
different.
Positional isomers
Two types of isomers:
arrangements of atoms in space is different.
Skeletal isomers
______ is used for preserving biological specimens
FORMALIN
Simplest ketone.
ACETONE
Simplest aldehyde and has one carbon atom
FORMALDEHYDE
_______ is the main ingredient in gasoline treatments
designed to solubilize water in the gas tank and allow it to
pass through the engine in miscible form.
ACETONE
PHYSICAL STATE AT ROOM TEMPERATURE
– C1-C2 aldehydes are gases
– C3 -C11 straight-chain aldehydes are liquids
Aldehydes
PHYSICAL STATE AT ROOM TEMPERATURE
– Lower molar mass ketones are colorless liquids
KETONES
Water molecules can hydrogen-bond with aldehyde and
ketone molecules, which causes low-molecular-mass
aldehydes and ketones to be water soluble.
SOLUBILITY
– Aldehydes readily undergo oxidation to carboxylic acids
Oxidation of Aldehydes and Ketones
Tollens reagent [aqueous
silver nitrate (AgNO3 ) and ammonia (NH3 )] when added to an
aldehyde, Ag+
ion is reduced to silver metal, which deposits
on the inside of the test tube, forming a silver mirror
TOLLENS TEST
Similar to the Tollens test except that the metal ion
oxidizing agent is Cu2+
BENEDICT’S TEST
Aldehydes and ketones are easily reduced by
hydrogen gas (H2), in the presence of a catalyst
(Ni, Pt, or Cu), to form alcohols
REDUCTION OF ALDEHYDES AND KETONES
Aldehydes and ketones react with alcohols to form
hemiacetals and acetals.
REACTION OF ALDEHYDES AND KETONES WITH ALCOHOLS
A hemiacetal is an organic
compound in which a carbon atom is bonded to both a
hydroxyl group (—OH) and an alkoxy group (—OR)
Hemiacetal formation
can also be formed due to the reaction
hemiacetal
An acetal is an organic compound in
which a carbon atom is bonded to two alkoxy groups (— OR)
Acetal Formation:
Undergo hydrolysis in acidic solution to
form the aldehyde or ketone and alcohols that originally
reacted to form the acetal.
Acetal Hydrolysis
is a prolific “polymer former
Formaldehyde
Replacement of carbonyl oxygen with sulfur produces ____ AND _______
thioaldehydes (thials) and thioketones (thiones)
________ is an odorless liquid with excellent solvent
properties
DMSO (dimethyl sulfoxide)
