Why base is used in aldol condensation?
Aldol condensation is an organic reaction in which an enolate ion reacts with carboxyl compound in order to form a β– hydroxy aldehyde or β– hydroxy ketone. Hydroxide functions as a base and therefore moves the acidic a-hydrogen producing the reactive enolate ion.
What is ethanol used for in aldol condensation?
e. In the lab, a solvent mixture of 95 \% ethanol and toluene (1:1) is used as the solvent for recrystallization. TPCP dissolves well at elevated temperatures but relatively poorly at low temperature in this solvent mixture.
Which base is used in aldol condensation in green synthesis?
The Aldol condensation is carried out by mixing freshly ground mixture of the lithium enolate of methyl-3,3-dimethylbutanoate with powdered Page 4 Green Synthesis of Organic compounds aromatic aldehyde in vacuum for 3 days at room temperature.
Why is NaOH used in aldol condensation?
NaOH it undergoes self condensation as it contains alpha-hydrogen atom in its compound forming β-hydroxyaldehyde (an aldol) namely 3-Hydroxy butanal. This compound upon further heating will eliminate a molecule of water forming aldol condensation product namely Crotonaldehyde Or But-2-en-al.
Why is ethanol included in the reaction solvent?
Ethanol is a very polar molecule due to its hydroxyl (OH) group, with the high electronegativity of oxygen allowing hydrogen bonding to take place with other molecules. Ethanol therefore attracts non-polar molecules. Thus, ethanol can dissolve both polar and non-polar substances.
What is the function of ethanol in this reaction?
The ethanol serves as a reactant to form the ethyl ester. 2. The ethanol is probably an excess reactant, so it also serves as a solvent. The most important reason for using absolute ethanol is that the Fischer esterification is an equilibrium reaction with a Keq≈4 .
Which gives aldol condensation reaction?
An aldol condensation is a condensation reaction in organic chemistry in which an enol or an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction), followed by dehydration to give a conjugated enone.
What solvent was used for this aldol reaction?
Aldol reactions may be carried out without use of preformed enolates simply by grinding together solid reagents in the presence of NaOH. No organic solvent (unless product recrystallisation is required) is utilised in the reaction and the only waste produced is a small amount of acidic aqueous waste.
What is the meaning of aldol reaction?
Aldol Reaction. ‘Aldol’ is an abbreviation of ald ehyde and alcoh ol. When the enolate of an aldehyde or a ketone reacts at the α-carbon with the carbonyl of another molecule under basic or acidic conditions to obtain β-hydroxy aldehyde or ketone, this reaction is called Aldol Reaction.
What is aldol condensation?
In aldol condensation, an enol or an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone (an aldol reaction ), concentration of the base is not predominately used to break the C=O bond. The aldol reaction involves removal of a reasonably acidic alpha proton and formation of a C-C bond.
How do you determine the structure of an aldol?
So, what you can do to determine the structure of the aldol is to draw the “V” shape β-hydroxy carbonyl and add the rest of the carbon chain to each side of this unit: More examples to practice this concept are given here: What if Different Carbonyl Compounds are Reacted in an Aldol Reaction?
What is the aldol product when acetaldehyde is added to benzaldehyde?
So, the aldol product is a result of a nucleophilic addition of the acetaldehyde enolate to benzaldehyde: All the other possibilities and details of the crossed aldol reaction will be covered in the following post: What is the Difference Between the Aldol Reaction and Aldol Condensation?