Advices For Studying Organic Chemistry

SUMMARY OF METHODS FOR THE PREPARATION

OF ALKENES AND ALKYNES

1. Dehydrohalogenation of alkyl halides (Section 7.6)
   General Reaction

CC

X

H

base CC

heat

(−HX)

Specific Examples
C 2 H 5 O−Νa+

CH 3 CH 2 CHCH (^3) C 2 H 5 OH
Br
H 3 CHC CHCH 3 + H 3 CH 2 CHC CH 2
(cis and trans, 81%)(19%)
(CH 3 ) 3 CO−Κ+
CH 3 CH 2 CHCH (^3) (CH 3 ) 3 COH
Br
H 3 CHC CHCH 3 + H 3 CH 2 CHC CH 2
Disubstituted alkenes
(cis and trans, 47%)(53%)
Monosubstituted alkene

2. Dehydration of alcohols (Section 7.7 and 7.8)
   General Reaction

CC

H OH H 2 O)

acid CC

heat

(−

Specific Examples

CH 3 CH 2 OH

concdH 2 SO 4

180 oC CH^2 =CH^2 +^ H^2 O^

H 3 CC OH

CH 3

CH 3

20% H 2 SO 4

85 oC H^3 CC CH^2

CH 3

+ H 2 O