Carboxylic Acids and Derivatives Flashcards
What are the most widely distributed acyl compounds?
Carboxylic acids
It is the most important of the acidic organic compounds
Carboxylic Acids
They contain the carboxyl groups as their functional groups
Carboxylic Acids
They are polar compounds and form very strong intermolecular hydrogen bonds
Carboxylic Acids
Values of pKa for most aliphatic and aromatic carboxylic acids fall within the range _______.
4 to 5
The greater acidity of carboxylic acids relative to alcohols, both of which contain an OH group, is due to__________of the carboxylate anion
resonance stabilization
It have a greater tendency to release a proton than
other acidic organic compound types.
Carboxylic Acids
They are considered as carboxylic acid functional derivatives because they are readily hydrolyzed to carboxylic acids.
Nitriles
_________ with fewer than five carbon atoms are soluble in water and form solutions that give an acidic response (pH < 7) when tested with litmus paper
Carboxylic acids
Solubility in 6M NaOH is a positive identification test for ________. A carboxylic acid that is ________ in pure water will be ________ in base due to the formation of the sodium salt of the acid as the acid is _______ by the base (high molecular weight).
acids , insoluble, soluble, neutralized
The reaction of an alcohol with a carboxylic acid
Esterification
A cyclic ester is called a _______
lactone
In the Esterification reaction, alcohols react with carboxylic acids to form fruity-smelling compounds called ________.
esters
The reaction is called esterification and is catalyzed by an acid such as __________.
concentrated H2SO4
By using a strong acid, an alcohol can react with a _________ to give an ester.
carboxylic acid (Fischer esterification)
In acid-catalyzed nucleophilic acyl substitution, the ________ the carbonyl oxygen on the carboxylic acid, and thus activates the carbonyl group to nucleophilic attack, leading to the ester hydrate.
strong acid protonates
Protonation of the hydroxyl group creates a superior leaving group, leading to _________ formation
ester
Alcohols react with acetyl chlorides to form esters and give out hydrogen chloride gas. What test it is?
Acetyl Chloride Test
Another positive test for acetyl chloride test is, the hydrogen chloride formed gives _______ of ammonium chloride with ammonium hydroxide.
white fumes
All acid derivatives yield carboxylic acids on ________.
Hydrolysis
The hydrolysis (in most cases) can either be ______ or _______ catalyzed
acid or base
The reactivity toward hydrolysis varies greatly amongst the __________.
derivatives
Positive Result: Evolution of heat after addition of H2O. Bubble (C)2) formation after addition of sodium bicarbonate.
Acid Hydrolysis
In this test, alcohols react with acetyl anhydrides to form esters and carboxylic acids
Hydrolysis of Acetyl Anhydride
The reaction is _________ because acid anhydride aren’t so violently reactive as acyl chloride
slower
It is a reaction with water where decomposition occurs dehydration - involves loss of water.
Hydrolysis
The acid catalyzed hydrolysis of an ester is simply the reverse reaction of the __________.
Fischer esterification
In hydrolysis of esters, addition of _______ drives the equilibrium towards the side of the acid and alcohol.
excess water
The basic hydrolysis of esters is also known as _________.
saponification
_________ are the most reluctant derivatives to undergo hydrolysis, but they can be forced to by the use of vigorous conditions such as heating with 6M HCL or 40% NaOH for prolonged periods of time.
Amides
Positive result: appearance of a blue color on the filter paper with ammonia or amine-like odor. After acidification, some compounds form precipitates or heterogenous mixtures. Observation of characteristic odor of carboxylic acids.
Base hydrolysis
In this test, if ethanamide is heated with NaOH solution, ammonia gas is given off and a solution containing sodium ethanoate
Base hydrolysis
The ________ vary greatly in their reactivity with nucleophiles.
carboxylic acid derivatives
Acid chlorides hydrolyze in moist air, whereas amides hydrolyze slowly, even in boiling alkaline water
True or False
True
The reactivity of acid derivatives depends on both the structures of the derivatives and also on the ___________. This order also correlates to the basicity of the _________.
Nature of the nucleophile
Leaving Group
It is easy to convert more reactive derivatives into less reactive derivatives.
True or False
True
An acid chloride is easily converted into an anhydride, ester, or amide, but an _____ can only be hydrolyzed to a carboxylic acid.
amide
All conversions involve _______________ via the addition elimination mechanism.
nucleophilic acyl substitution
It is a reaction of acyl chloride and acid anhydride with primary amines.
Anilide formation
Positive Result: Formation of anilide precipitate
Anilide formation
Carboxylic acids react with sodium bicarbonate to produce carbon
dioxide gas which can be seen in the form of a brisk effervescence.
Sodium Bicarbonate Test
Positive Results: Formation of bubbles (presence of CO2)
Sodium Bicarbonate Test
