General Organic Chemistry

Why do aromatic compounds with nucleophilic groups bonded directly to the aromatic ring not undergo nucleophilic substitution reactions under ordinary conditions?

Due to the high electronegativity of the leaving group.
Due to the presence of a π bond on the key atom of the functional group. (correct)
Because of the electron-donating nature of the aromatic ring.
Because the nucleophilic group is sterically hindered.

What is the order of reactivity of alkyl halides in SN1 reactions?

Methyl > 1° > 2° > 3°
3° > 2° > 1° > methyl (correct)
1° > 2° > 3° > methyl
2° > 1° > 3° > methyl

What is the rate-determining step in an SN2 reaction?

The dissociation of the leaving group.
The formation of a transition state. (correct)
The back-side attack of the nucleophile on the substrate.
The collision between the substrate and nucleophile.

What is the key difference between SN1 and SN2 reactions in terms of molecularity?

SN1 is unimolecular, while SN2 is bimolecular. (D) Signup and view all the answers

Why do aromatic rings exhibit low nucleophilic character?

Due to the delocalization of electrons in the ring. (C) Signup and view all the answers

What is the stereochemical outcome of an SN2 reaction?

Complete inversion of configuration. (A) Signup and view all the answers

What is the mechanism of formation of benzyne intermediate?

Dehydrohalogenation (B) Signup and view all the answers

What is the nature of the ground state of nitrenes?

Triplet (B) Signup and view all the answers

What is the reactivity of benzyne intermediate?

Dienophilic (A) Signup and view all the answers

What is the byproduct of Hofmann-bromamide reaction?

Isocyanate (B) Signup and view all the answers

What is the role of sodium hydroxide in Hofmann-bromamide reaction?

Acts as a base (A) Signup and view all the answers

What is the method of generation of nitrenes mentioned in the text?

By action of Br2 in presence of a base on a 1 o amide (C) Signup and view all the answers

What is the hybridization of a carbocation?

sp2 (C) Signup and view all the answers

What is the stability order of carbanions?

Ph3C > Ph2CH > PhCH2 > PhCH3 (C) Signup and view all the answers

What is the magnetic property of a carbocation?

Paramagnetic (A) Signup and view all the answers

What is the structure of a carbene in its triplet state?

Linear (B) Signup and view all the answers

What is the nature of the aryne intermediate?

A neutral reaction intermediate (B) Signup and view all the answers

What is the name of the simplest member of the aryne family?

Benzyne (D) Signup and view all the answers

What is the major product of an E2 reaction, according to Saytzeff rule?

The most substituted alkene (C) Signup and view all the answers

Why does rearrangement not take place in E2 reactions?

Because the reaction occurs in one step, prohibiting rearrangement (C) Signup and view all the answers

What is the role of the polar aprotic solvent in an E2 reaction?

To stabilize the transition state (A) Signup and view all the answers

What is the orientation of the product in a β-elimination reaction?

The product is oriented in a way that the most substituted alkene is formed (C) Signup and view all the answers

What is the characteristic of the product obtained by elimination of H from the β-carbon having the least number of hydrogen?

The product is the most substituted alkene (C) Signup and view all the answers

What is the primary difference between the product formation in E1 and E2 reactions?

E1 reactions only follow Saytzeff rule, while E2 reactions can follow both Saytzeff and Hofmann rules. (A) Signup and view all the answers

In the given E2 reaction, what is the role of the base?

The base helps in the formation of the transition state. (D) Signup and view all the answers

What is the characteristic of the product formed in E2 reactions according to Hofmann rule?

The product is always the least substituted alkene. (D) Signup and view all the answers

What is the rate law expression for an E2 reaction?

Rate ∝ [Substrate] [Base] (C) Signup and view all the answers

What is the key difference between E1 and E2 reactions?

E1 reactions are unimolecular, while E2 reactions are bimolecular. (A) Signup and view all the answers

What is the significance of the β-carbon in the given reaction?

The β-carbon has the maximum number of hydrogen atoms. (C) Signup and view all the answers

What is the condition for an alkene to undergo an addition reaction according to Markownikoff's rule?

Alkene should be unsymmetrical. (C) Signup and view all the answers

What is the effect of a strong -I group on the addition reaction of an unsymmetrical alkene?

It promotes the addition reaction according to Anti-Markownikoff's rule. (D) Signup and view all the answers

What is the reason for the polarity of the carbon-oxygen double bond in a carbonyl group?

Due to the presence of a strongly electronegative oxygen atom. (B) Signup and view all the answers

What is the type of addition reaction that occurs when a nucleophile attacks the carbon atom of a carbonyl group?

Nucleophilic addition reaction (D) Signup and view all the answers

What is the effect of the electronegative oxygen atom on the carbon atom of a carbonyl group?

It makes the carbon atom electron-deficient. (C) Signup and view all the answers

What is the example of a nucleophilic addition reaction mentioned in the text?

The addition of HCN to acetone. (C) Signup and view all the answers