Organic Chemistry Chapter 16
Carboxylic Acid Derivatives (in order from most reactive to least reactive)
Acid Halides
Anhydrides
Esters
Amides
Anhydrides
Esters
Amides
Chemically Made
Acid Halides
Anhydrides
Anhydrides
Crucial to Biological Life
Esters
Amides
Amides
Rules of Carboxylic Acid Derivatives
Can all be turned back into carboxylic acid w H2O (hydrolysis)
Can’t go backwards (amide to halide)
Can convert forward
all have leaving groups
Can’t go backwards (amide to halide)
Can convert forward
all have leaving groups
Leaving Group of an acid halide
halogen
Leaving Group of esters
OR group or everything to the right of the carbonyl group
Leaving Group of Amides
Nitrogen group attached to the carbonyl group
Rules for Resonance Structures
number through the double bond to atom with lone pair or charge
Keep simple skeletal structure
ONLY MOVE SINGLE SET OF ELECTRONS
Keep simple skeletal structure
ONLY MOVE SINGLE SET OF ELECTRONS
Fatty Acids with more than one double bond
have C=C bond
have C=C bond
poly unsaturated
When have no C=C bond fatty acids are
saturated with H.
Fatty Acids
Carboxylic acids with long hydrocarbon chains
Saturated Fatty Acids
Solids clog arteries unhealthy.
have high melting point
No C=C bond
have high melting point
No C=C bond
Unsaturated Acids
Have low melting points
liquid chains so flow through blood stream.
have C=C bond
liquid chains so flow through blood stream.
have C=C bond
Y Group
Electronegative Group
R Group
Leaving Group
Tetrahedral groups are unstable because
3 E.N. groups on Carbon.
Best leaving groups in order from greatest to least
acid halides (least basic)
anhydrides
esters
amides (most basic)
anhydrides
esters
amides (most basic)
Products of Ester Hydrolysis
A carboxylic acid or alcohol or get them together
Leaving Groups of Anhydride
Everything to the right of Carbonyl Group
Smaller the pka the ___ the acid
Smaller the pka the stronger the acid
Nucleophiles must have
Lone pair
Ester hydroylsis an be increased by
basic/acidic conditions
Ester Hydroylsis Exception
When 3 (tertiary) group comes from oxygen – does not require tetrahedral mechanism
Ester Hydrolysis yields
Carboxylic acid/alcohol/or both
What requires CH3CH2OH excess, H+ catalytic acid, and heat, and tetrahedral mechanism
Fischer Esterfication
Nylon
N attached to a C double Bond to O
Amides are most/least reactive
Least Reactive
Amides are less/very stable
VERY STABLE
Characteristics of Amides
Least Reactive
Hardest to degrade
Very Stable
Hardest to degrade
Very Stable
Can make an amide from which carboxylic acid derivatives
Any of them
Amides can or cannot go through hydrolysis
can not go through hydrolysis Very resistant Very Slow
Only can be hydrolyzed if pH very low
Only can be hydrolyzed if pH very low
Gabriel Synthesis
Hydrolysis of Imides
Takes imides and turn them into primary amine
Takes imides and turn them into primary amine
SOCl2
convert carboxylic acid into a carbochloride
PBr3
turn carboxylic acid into acid bromide
Relative Basicities of Leaving Groups
Cl-<-OR=-OH< -NH2
with Cl being the weakest base and NH2 being the strongest.Therefore Cl is the best leaving group.
Relative Reactivites of Carboxylic Acid Compounds
Acyl Chloride > Ester> Carboxylic Acid > Amide
Acyl Chloride: most reactive
Amide: least reactive
Acyl Chloride: most reactive
Amide: least reactive
Acyl chloride reacts with alcohols to form
Esters
Acyl chloride reacts with H2O to form
Carboxylic Acids
Acyl Chloride reacts with Amine Group to form
amides
An ester reacts with water to form a
Carboxylic Acid and Alcohol
An ester reacts with alcohol to form a
new ester and a new alcohol
Esters react with amines to form
amides
Carboxylic acids react with alcohols to form
esters
Can Amines undergo fisher esterification?
NO
What reaction prepares a primary amine from an alkyl halide.
Gabriel Synthesis