In the following carbocation, H/CH3 that is most likely to migrate to the positively charged carbon is
A) CH3 at C-4
B) H at C-4
C) CH3 at C2
D) H at C2
1thr is no conjugation....so o of oh shows -i effevt and increase charge on the carbocation formed causing decrease in stability
1migratory aptitude is directly proportional to nucleophilicity.....1)
a carbocation that is near an atom having a lone pair of e- like o or N is more stable than a 3° carbocation (reason there forms a c=0+ where there is a + charge on O..in this case the octet of all the atoms is complete)......2)
using these two statements, we can say that the answer shud be D)
11arey....i know that CH3 and OH groups have opposite effects........and that CH3 releases electrons......so OH's gotta withdraw them ....... so how'll it help the stability of the carbocation??
1answer is D
because + charge on carbon bearing -OH is most stable as O as lone pair of electrons... Think of pinacol pinacolone rearrangement
1C4
Is rite
just q of h or ch3
but i think ch3 is more common
n seeeing situations , h i s stable , n so ch3 is too
but ch3 can make it more stable , i donno y but i can feel it
A
11If H at C4 goes as H- to the carbocation (hydride shift) then, the positive charge will move to a tertiary position and will become more stable....so i think answer is b
62[url=http://iitjee2009solutions.targetiit.com]Solution Key with Question Paper of 2009 IIT JEE[/url]
1but how com yaaaar?
in C2
ders OH
n it will pull elektron
then y will methy or go fm C2?
then definately
C4 naaaaaaaaaa ?
then only
H OR METHYL
naaaaaa
but methyl is more efficient
then
A
