got it. thx guys
parts a,b(i) and b(ii) are rightJ_o_S said:For a) I was thinking I could just show that both reaction mechanisms add up to the same reaction.
for b)i) I think the reaction rate would triple, for b)ii) I dont think the reaction rate would change.
not sure about part c
Can anyone point me in the right direction?
siddharth said:J_o_s: First of all, its 1-propene. Refer the IUPAC nomenclature rules.
Then, look at the structure of propene. The carbon-carbon double bond is rich in electrons. And HBr is an acid. Therefore, where will the H+ ion attack? What's the intermediate formed? Have you learned about carbocations and their rearrangments?Then what will the Br- do?
Also, have you learned about Markovnikov rule.?
Dr Brain: it's an Electrophilic Addition reaction.
A reaction in which the substrate and the reagent add up to form a product is called addition reaction.Dr.Brain said:siddharth , this is a two stage process ,first the double bond is broken and then Br- attacks.In addition processes, the attack and leaving processes both take place simultaneously.
Leaving process is in substitution and not in addition , have you heard ofsiddharth said:A reaction in which the substrate and the reagent add up to form a product is called addition reaction.
In this case, HBr is the reagent and propene is the substrate.
Where is the leaving process in the addition reaction?
Let's go through the definitions againDr.Brain said:Leaving process is in substitution and not in addition , have you heard of
[itex]S_N - 1[/itex] and [itex]S_N - 2[/itex] ... ? , the same happens here.
You said it all. In the above reaction if it had been a complex substrate other than propene, the carbocation re-arrangement would have taken place, and after the [itex]C^+[/itex](ii) Nucleophilic substitution
Here one nucleophile is displaced by another.
R-X + OH- ----------> R-OH + X-
This reaction can proceed under two major mechanisms, namely the SN1 and SN2 mechanisms. SN1 is a first order reaction and follows first order kinetics whereas SN2 is a second order reaction and follows second order kinetics.
Apart from this there is also the SNi mechanism or Substitution Nucleophilic Internal mechanism.
In the above reaction the attacking species is OH- and the leaving group is X-