Advices For Studying Organic Chemistry

1. When alkenes are treated with cold concentrated sulfuric acid, they dissolve


2. T dition of HX:
   1 n
   c
   2) In the second step, the carbocation reacts with a hydrogen sulfate ion to form an

because they react by addition to form alkyl hydrogen sulfates.

he mechanism is similar to that for the ad

) I the first step, the alkene accepts a H+ form sulfuric acid to form a

arbocation.

alkyl hydrogen sulfate.

CCH OSOH

O

O

+ C C

H

+ + OSOH

O

O

− C C

HO 3 SO H

Alkene Sulfuric acid Carbocation Hydrogen sulfate ion Alkyl hydrogen sulfate

Soluble in sulfuric acid

3. The addition of H 2 SO 4 is regioselective and follows Markovnikov’s rule:

CCH 2
H 3 C

H

H OSO 3 H

CCH 2

H 3 C

H

H

OSO 3 H

+

−

H 3 C C

H

CH 3

OSO 3 H

2 o Carbocaion Isopropyl hydrogen sulfate

(more stable carbocation)

8

1. by heating them

.4A ALCOHOLS FROM ALKYL HYDROGEN SULFATES:

Alkyl hydrogen sulfates can be easily hydrolyzed to alcohols

with water.

CH 3 CH CH (^2) Hcold
H 2 O,hea
2 SO 4
t CH 3 CHCH 3 H 2 SO 4
OH
CH 3 CHCH 3 +

1. addition of sulfuric acid to an alkene followed by
   OSO 3 H
   The overall result of the