Here I come up with sets of rules that will make you Conversion Problems cakewalk. These rules will definitely make you work in a particular direction so that you need to think less in the pressure of tickling clock in exam hour. So, enjoy SM way to Crack supposedly most difficult question type in NEB Board.
Conversion Type 1: Constant Carbon Conversion
Rule 1: Common rules for all conversion:
A) Juxtapose the structure of compounds in questions.
B) Write suitable intermediates to connect the structures written in Step A
C) Connect with forwarding arrows.
D) Fill up the reagents along arrow
D) Complete answer by all reactions involved with side products
Rule 2: If one is stuck in alkane, make sure you immediately change it to haloalkane. so that compound becomes flexible and can be easy to change to various Organic compounds.
Rule 3: If conversion ends at nitroalkane, convert immediately to amine and then to alcohol using the following sequence of reactions.
Rule 4: Similarly if the conversion is from Grignard to the compound having the same number of Carbon as a Grignard reagent. Be sure to use the following reaction to free from Mg.
Rule 5:Equip yourself with these 15 reactions that are most common in use in Conversion related Problems of any kind (Aliphatic).
Rule 6: If Conversion involves Positional isomers, it always involves alkene.
A) Juxtaposing structures of compounds in the question
B)Write the structure of suitable alkene in the middle then only proceed.
C) If you have to prepare alkene chose haloalkane and if you want a product from alkene chose haloalkane.
D) Be sure while preparation of haloalkane from alkene choose bromoalkane because both Markovnikov, as well as Antimarkovkikov rule, exist for the addition of HBr to alkene depending on the scenario.
E) then make changes as per requirement choosing any one of the 15 keys chemical reactions.
For example:
i)Conversion of 1-propanol to 2-propanol
A) Juxtaposing structures of compounds in the question/ Write the structure of 1-propanol and 2-propanol side by side.
B) Write the Structure of suitable alkene in the middle/in this case, its Propene.
C) Prepare alkene with haloalkane & Prepare haloalkane from alkene.
D) Now connect with arrows in the forward direction with suitable reagents
E) Write the reactions involved with side products as:
Similarly, Conversion of 2-propanol to 1-propanol as:
Reactions involved:
iii) Conversion Of Ethyl Magnesium bromide into Ethanoic acid.
iv) Conversion Of 1-bromopropane to 2-bromopropane
v) Conversion Of 1-chloropropane to 2-chloropropane
This site provides notes on different chapters of Chemistry of Grade XI and XII (NEB Board). Also, it posts number of blogs on Collection of past questions and solution. Conversion chart, rules, Chemical test are some additional features.
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