Question

64.
Arrange the reactivity of given compounds in decreasing order for electrophilic addition reaction
CH-C=CH2
P
1)
CH;
2) HỌC = CII-CH,
A.
CoHC=C-CH3
Н
CH,
3)
4) H,C = CH - NO,
C) 2,3,1,4
A) 4.1.2.3
B) 3,1,2,4
D) 2,3,4,1​

Answer 1

Explanation:

The order of electrophilic addition (EA) is alkene > alkyne. But, if alkene has EWG (electron-withdrawing group) reactivity of alkene is less than that of alkyne.

Due to EWG electron density at (C=C) or nucleophilicity decreases, so addition of electrophile to (C=C) is slow.

So, the decreasing order of EA is:

(II) - (alkene) > I - (alkyne) > III - (alkene with one EWG) > (IV) - (alkene with two EWGs).