Concept explainers
Interpretation:
The resonance structure for the anion of acetonitrile, which is more acidic than ethane, is to be written and step-by-step mechanism for the condensation of benzaldehyde with acetonitrile is to be given.
Concept introduction:
舧 Electrophiles are electron-deficient species, which has positive or partially positive charge. Lewis acids are electrophiles, which accept electron pair.
舧 Nucleophiles are electron-rich species, which has negative or partially negative charge. Lewis bases are nucleophiles, which donate electron pair.
舧 Free radical is an atom, molecule, or ion that has an unpaired electron, which makes it highly chemically reactive.
舧 Substitution reaction: A reaction in which one of the hydrogen atoms of a hydrocarbon or a
舧 Elimination reaction: A reaction in which two substituent groups are detached and a double bond is formed is called elimination reaction.
舧 Addition reaction: It is the reaction in which unsaturated bonds are converted to saturated molecules by the addition of molecules.
舧 In nitrile, alpha hydrogen is weakly acidic, so the nitrile undergoes aldol-type condensation.
舧 A carbon-carbon bond formation occurs by aldol addition and aldol condensation reaction.
舧 An aldol reaction takes place by acid catalysis, and direct dehydration of
舧 A
舧 A chemical reaction that is catalyzed by a base is called base-catalyzed reaction.
舧 Aldol reaction is preferred in basic condition over acidic condition as after the aldol condensation, acid catalysis promotes the reaction further.
舧 An aldol reaction takes place in a protic solvent with a base.
舧 Dehydration of aldol addition product leads to the formation of conjugated
The rules for drawing resonance structures are as follows:
舧 Only nonbonding electron pairs and pi electrons can participate in conjugation in the formation of various resonating structures.
舧 The single bonds present in the molecule do not break or form in the resonance structures.
舧 The placement of atoms present in the molecule remains fixed.
舧 The octet of all atoms is completely filled.
舧 More the number of resonance structures indicate higher stability of a compound.
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Organic Chemistry
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