Nucleophilic Substitution in Alkyl Halides

Q. The organic chloro compound, which shows complete stereochemical inversion during a $S_{N}2$ reaction, is

1. $(C{H}_3{)}_{2}CHCl$
2. $C{H}_{3}Cl$
3. $\left(C_2{H}_5\right)CHCl$
4. $(C{H}_3{)}_{3}CCl$

Q.

The order of reactivity of the following alkyl halides for an SN² reaction is

1. RF > RCl > RBr >RI

2. RCl > RBr > RF > RI

3. RF > RBr > RCl > RI

4. RI > RBr > RCl > RF

Q.

Which one is most reactive towards SN¹ reaction?

1. C₆H₅CH₂Br

2. C₆H₅CH(Br)C₆H₅

3. C₆H₅CH(CH₃)Br

4. C₆H₅C(CH₃)(C₆H₅)Br

Q.

tert-alkyl halides are practically inert to substitution by SN2 mechanism because of:

1. Insolubility

2. Instability

3. Inductive effect

4. Steric hindrance

Q.

Which of the following ether will always give SN_2 mechanism in acidic as well as basic conditions ?

1. 

2. 

3. 

4. All

Q. $C_6{H}_5-\stackrel{\underset{|}{C{H}_3}}{\underset{\stackrel{|}{H}}{C}}-Br+H_{2}O⟶HO-\stackrel{\underset{|}{C{H}_3}}{\underset{\stackrel{|}{H}}{C}}-C_6{H}_5+HBr$
The above reaction results in 98% racemization. The reaction mainly follows

1. ${S_N}^1$ mechanism
2. ${S_N}^2$ mechanism
3. $E^1$ mechanism
4. $E^2$ mechanism

Q.

Predict all the possible products for the reaction of 2-chlorobutane with alcoholic $KOH$.

1. 1-Butene
2. Cis-2-butene
3. Trans-2-butene
4. 2-Butyne

Q. Which of these alkyl halides will undergo $S_{N}1$ reaction at the fastest rate?

1. $Cl-C{H}_2-CN$
2. $Cl-C{H}_2-N{O}_2$
3. $Cl-C{H}_2-OMe$
4. $Cl-C{H}_2-C{H}_3$

Q. Which of the following compounds would not give ppt. with $AgN{O}_3$

1. $C{H}_{3}CH=CHCl$
2. $C{H}_2=CH-C{H}_{2}Cl$
3. 
4. $(C{H}_3{)}_{3}CCl$

Q. The organic chloro compound, which shows complete stereochemical inversion during a $S_{N}2$ reaction, is

1. $(C{H}_3{)}_{2}CHCl$
2. $C{H}_{3}Cl$
3. $\left(C_2{H}_5\right)CHCl$
4. $(C{H}_3{)}_{3}CCl$

Q.

When ethyl chloride is added to Sodium tert-butoxide, ethyl tert-butyl ether is obtained as the major product (shown below):

When the concentration of ethyl chloride is doubled, the reaction rate:

1. quadruples

2. halves

3. remains unchanged

4. 
   doubles

Q. Which of the following will give the fastest nucleophilic substitution reaction by $S_{N}2$ pathway ?

1. 
2. 
3. 
4. 

Q.

which one of the given options would convert propylbenzene into (1-methoxypropyl)benzene:

1. cumene with NBS and a radical initiator or light; followed by treatment with methoxide

2. ethylbenzene with NBS and a radical initiator or light; followed by treatment with methoxide

3. propylbenzene with NBS and a radical initiator or light; followed by treatment with methoxide

4. A and C

Q.

The reaction of benzyl chloride with sodium cyanide followed by reduction with hydrogen in the presence of nickel give

1. Phenylethylamine

2. N-Isobutylaniline

3. Benzylamine

4. Aniline

Q.

The reaction R - Br + NaCN → R-CN + NaBr, is an example of

1. Elimination reaction

2. Nucleophilic Substitution

3. Electrophilic substitution

4. Oxidation - reduction

Q.

Which of the following will give a faster solvolysis in aqueous ethanol more rapidly?

1. Neither I nor II undergo ethanolysis

2. Both undergo ethanolysis at the same rate

3. I

4. II

Q.

Which of the following undergoes nucleophilic substitution exclusivelyby S_N1 mechanism?

1. Ethyl chloride

2. Isopropyl chloride

3. Chlorobenzene

4. Benzyl chloride

Q.

Observe the given compound.

Which of the following is best suited to synthesize the compound via an $S_{N}2$ reaction?

1. 

2. 

3. 

4. 

Q.

Draw Fischer projections for the following $S_{N}2$ substitution reaction:

1. At the chiral center where substitution happens, .inversion of stereochemical configuration occurs

2. At the other chiral center, .retention of stereochemical configuration occurs

3. At the chiral center where substitution happens, .retention of stereochemical configuration occurs

4. At the other chiral center, .inversion of stereochemical configuration occurs

Q.

$S_{N}1$ solvolysis of 1-(bromomethyl)cyclohex-1-ene in ethanol gives:

1. The reaction produces a single major product

2. The reaction produces several products in nearly equal proportions

3. The reaction proceeds via a resonance-stabilized carbocation

4. The reaction is $S_{N}2$

Q.

Assume you get to start with an alkyl halide. To synthesize the following via a single-step $S_{N}2$ reaction,
which of the following options is appropriate ?

1. chlorocyclohexane is made to react with traces of ammonia

2. (chloromethyl)cyclohexane is made to react with traces of ammonia

3. (chloromethyl)cyclohexane is made to react with an excess of ammonia

4. chlorocyclohexane is made to react with an excess of ammonia

Q.

Assume you get to start with an alkyl halide. To synthesize the following via a single-step $S_{N}2$ reaction,
which of the following options is appropriate ?

1. chlorocyclohexane is made to react with traces of ammonia

2. (chloromethyl)cyclohexane is made to react with traces of ammonia

3. (chloromethyl)cyclohexane is made to react with an excess of ammonia

4. chlorocyclohexane is made to react with an excess of ammonia

Q. Which among the following compounds will undergo $S_{N}2$ reaction at the fastest rate ?

1. $({\mathrm{CH}}_3{)}_3\mathrm{CCl}$
   
2. $({\mathrm{CH}}_3{)}_2\mathrm{CHCl}$
   
3. ${\mathrm{CH}}_3\mathrm{Cl}$
   
4. ${\left(C_2{H}_5\right)}_2\mathrm{CHCl}$
   

Q. Consider the reaction
$C{H}_{3}C{H}_{2}C{H}_{2}Br+NaCN\to C{H}_{3}C{H}_{2}C{H}_{2}CN+NaBr$
This reaction will be the fastest in:

1. N, N-dimethylformamide (DMF)
2. water
3. ethanol
4. methanol

Q.

Comment on the following reactions
$\left(i\right)C{H}_{3}OH+NaCl\to \left(ii\right)C{H}_{3}OH+HCl\to$

1. Both reactions take place easily

2. Only reaction (ii) takes place

3. Reaction (ii) takes places faster than (i)

4. None of the two reactions in possible

Q.

Which of the following compounds does not undergo nucleophilc substitution reactions?

1. Ethyl bromide

2. Vinyl chloride

3. Isopropyl chloride

4. Benzyl chloride

Q.

Which of the following will undergo a faster $S_{N}2$?.

1. Both undergo $S_{N}2$ at the same rate

2. I

3. Neither I nor II

4. II

Q.

$BrC{H}_{2}CHBrC{H}_{2}Br\stackrel{alc.KOH}{\to }\left[X\right]\stackrel{C{H}_3{O}^{-}}{\to }Y;\left[X\right]$ and [Y] respectively are

1. $H_{2}C=CBrC{H}_{2}Br,H_{2}C=C\left(Br\right)C{H}_{2}OC{H}_3$

2. $H_{2}C=CBrC{H}_{2}Br,H_{2}C=C\left(OC{H}_3\right)C{H}_{2}Br$

3. $BrHC=CHC{H}_{2}Br,C{H}_{3}OCH=CHC{H}_{2}Br$

4. $BrHC=CHC{H}_{2}Br,BrCH=CHC{H}_{2}OC{H}_3$

Q.

Comment on the following reactions
$\left(i\right)C{H}_{3}OH+NaCl\to \left(ii\right)C{H}_{3}OH+HCl\to$

1. Both reactions take place easily

2. Only reaction (ii) takes place

3. Reaction (ii) takes places faster than (i)

4. None of the two reactions in possible

Q. Which is the correct energy profile diagram for the following solvolysis reaction?

1. 
2. 
3. 
4.