Get Answers to all your Questions

header-bg qa

Which of the following is the correct order of decreasing S_{N}2  reactivity?

  • Option 1)

    R_2CHX> R_3C\, X> RCH_2X

    ( X is a halogen)

  • Option 2)

    RCHX> R_3CX> R_2CHX

    ( X is a halogen)

  • Option 3)

    RCH_2X> R_2CHX> R_3CX

    ( X is a halogen)

  • Option 4)

    R_3CX> R_2CH X> RCH_2X

    ( X is a halogen)

 

Answers (1)

best_answer

As we learnt ,

 

Reactivity Order of alkyl halides -

1^{\circ}Alkyl\: Halide> 2^{\circ}Alkyl\: Halide> 3^{\circ}Alkyl \: Halide

 

- wherein

1^{\circ}Alkyl\: Halide> 2^{\circ}Alkyl\: Halide> 3^{\circ}Alkyl \: Halide

Inhibition by steric hindrance SN2 reactions are particularly sensitive to steric factors, since they are greatly retarded by steric hindrance (crowding) at the site of reaction. In general, the order of reactivity of alkyl halides in SN2 reactions is: methyl  > 1> 2o> 3o

 

 

 Lesser the steric hindrance at c faster the SN2 reaction rate .

So the correct order is :

RCH_2X> R_2CHX> R_3CX

 


Option 1)

R_2CHX> R_3C\, X> RCH_2X

( X is a halogen)

Option 2)

RCHX> R_3CX> R_2CHX

( X is a halogen)

Option 3)

RCH_2X> R_2CHX> R_3CX

( X is a halogen)

Option 4)

R_3CX> R_2CH X> RCH_2X

( X is a halogen)

Posted by

prateek

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE