Advertisements
Advertisements
प्रश्न
Distinguish between SN1 and SN2 mechanism of substitution reaction.
Advertisements
उत्तर
| Factor | SN1 | SN2 |
| Kinetics | 1st order | 2nd order |
| Molecularity | Unimolecular | Bimolecular |
| Number of steps | Two steps | One step |
| Bond making and bond breaking | First the bond in the reactant breaks and then a new bond in the product is formed. | Simultaneous |
| Transition state | Two steps, two transition states | One step, one transition state |
| Direction of attack of nucleophile | Backside attack and frontside attack | Only back side attack |
| Stereochemistry | Racemisation (If the substrate is optically active) | Inversion of configuration (If the substrate is optically active) |
| Type of substrate | Mainly 3° substrates | Mainly 1° substrate |
| Polarity of solvent | Polar protic solvent favorable | Aprotic (non-polar) or solvent with low polarity favourable |
| Intermediate | Intermediate involved | No intermediate |
APPEARS IN
संबंधित प्रश्न
Complete the following reaction giving major product.
\[\begin{array}{cc}\ce{CH3\phantom{................}}\\
|\phantom{...................}\\
\ce{CH3 - C - CH2 - Cl ->[Na/dry ether] A}\\
|\phantom{...................}\\
\ce{CH3\phantom{................}}
\end{array}\]
Name the reagent used to bring about the following conversion.
Bromoethane to ethoxyethane
Arrange the following in the increasing order of boiling points.
- 1-Bromopropane
- 2- Bromopropane
- 1- Bromobutane
- 1-Bromo-2-methylpropane
Convert the following:
Benzyl alcohol to benzyl cyanide
Convert the following:
2-Chloropropane to propan-1-ol
Convert the following:
tert-Butyl bromide to isobutyl bromide
Observe the following and answer the question given below.

Comment on the bond length of C–X bond in it.
The following will react faster by SN1 mechanism
Major product of the following reaction is _______________
\[\ce{CH3-CH2-Mg-Br + NH3 ->?}\]
Nucleophilic substitution reaction of 2, 4-dinitrochlorobenzene is faster than p-nitrochlorobenzene. Give reason.
Explain the factors affecting SN1 and SN2 mechanism.
Explain aqueous alkaline hydrolysis of tert. butyl bromide.
Dehydrohalogenation of an alkyl halide is ____________.
Nitroalkanes are obtained in laboratory from primary or secondary alkyl halides by the action of ______.
Which one is most reactive towards nucleophilic addition reaction?
Which of the following carbocation is the most stable?
When C2H5Br is treated with excess of alc. NH3, the major product obtained is ____________.
The SN2 reaction of a compound containing an asymmetric carbon atom always gives ____________.
Identify major product 'B' in the following reaction.
\[\ce{But-1-ene ->[HBr][Peroxide] A ->[AgCN][\Delta] B}\]
The order of reactivity of the given haloalkanes towards nucleophiles is:
Which among the following statements is not correct about SN2 reaction mechanism?
Complete the following reactions giving a major product.
\[\begin{array}{cc}
\ce{CH3}\phantom{................}\\
|\phantom{..................}\\
\ce{CH3 - C - CH2 - Cl ->[Na/dry ether] A}\\
|\phantom{..................}\\
\ce{CH3}\phantom{................}
\end{array}\]
Complete the following reaction sequences by writing the structural formulae of the organic compounds 'A', 'B' and 'C'.
\[\ce{2-Bromobutan ->[alc. KOH] A ->[][Br2] B ->[][NANH2] C}\]
Complete the following reactions giving major product.
\[\begin{array}{cc}
\ce{CH3}\phantom{................}\\
|\phantom{...................}\\
\ce{CH3 - C - CH2 - Cl ->[Na/dry ether] A}\\
|\phantom{...................}\\
\ce{CH3}\phantom{.................}
\end{array}\]
What is the action of following on ethyl bromide?
alcoholic sodium hydroxide
Complete the following reaction giving major product.
\[\begin{array}{cc}
\ce{CH3}\phantom{................}\\
|\phantom{...................}\\
\ce{CH3 - C - CH2 - Cl->[Na/ dry ether]A}\\
|\phantom{...................}\\
\ce{CH3}\phantom{................}\\
\end{array}\]
