Organic Chemistry – Nucleophilic Substitution – Alkyl Halides

I will be very honest with all of you. I didn’t start my journey of organic reaction mechanisms with the standard method. Usually, kids start of mechanisms with Hydrocarbons (addition/free radical substitution, etc). I started my journey of Reaction Mechanisms with Nucleophilic Substitution reactions. The chapter was Alkyl Halides and there were a number of concepts to be learned – Sn1, Sn2 and Sni reactions, along with the use of Neighbouring Group Participation (NGP). These are definitely the OST important concepts of this chapter and enough attention must be given on them.

Tips for the Chapters :

  • The first thing to keep in mind is the characteristics of each of the reaction mechanisms – Sn1, Sn2 and Sni. The important characteristics are – stereochemistry of the reaction, direction of attack, orientation of the leaving group with the attacking group, effect of bulky substituents, effect of polarity of solvent and effect of neighbouring groups. 
  • Second most important thing is Carbocation Rearrangements and Ring Expansion/Contraction. 
  • Also, I would strongly advise you to prepare a table listing the properties and differences of SN1 and SN2 reactions side by side. Memorise this table well as it would aid you in solving questions based on mechanisms easily. Just a few concepts are enough to master this chapter. Provided you practice a lot.
  • The Important Named Reactions of this Chapter are – Darren Reaction, Finkelstein Reaction, and Walden Inversion.


Books that are essential for this chapter are the same as the ones I have recommended for Organic at all other places –


Practice a lot from these books to master the concepts of this chapter. All the best !

Aakash Kapoor.

27 thoughts on “Organic Chemistry – Nucleophilic Substitution – Alkyl Halides”

  1. Answer honestly …

    Did you solve only ms chouhan ?
    And one more thing lg wade has lot of rxn missing ..perkin cannizarro etc. What for these

  2. Are the Level 2 questions of M S Chouhan relevant for Advanced? The author himself has mentioned that the are ‘ altogether different from the prevailing trend followed by JEE ‘.

  3. As this part requires stereochemistry. how can i improve stereochemistry overall? i am unable find satisfactory theory in lg wade and fiitjee rsm.

  4. Why did you started with alkyl halide ?
    I am finding that in few chapters like alkene various concepts of elimination is being used.

    When was your organic syllabus was over ?

    1. Personal Choice.
      I don’t remember when it got over, simply because it’s so inter related that I could easily do it

  5. I am afraid I am very scared of the whole Organic Chem thing especially Nucleophillic Subs. It just intimidates me, and I struggle when I do exams,can you say something that can improve this situation. I am in 12th now.

  6. I have lg wade and I use it from class 11 th ( now I’m in 12th ) I have one more book ranjeet shahi arihant …I found that It has very good.examples..I had been using it these days.. I am confused..will lg wade + ms chauhan + RESONANCE material

  7. Is doing resonance material(everything in it starting from NCERT type,Subjective, MCQ ‘S single, more than one option ,passage, matrix etc to previous yr questions or jee n Olympiads )enough for jee mains +advanced?

    1. Can’t say. Much depends on how you use it. As far as theory coverage and question practice is concerned, I suppose it is.

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