2. Preparation of Alkanes via
Reduction
Hydrogenation of Alkenes
Hydrogenation of Alkynes
R R' R R'
H2 /Pt
C C CH CH
R R' R R'
H H
H2 /Pt
R C C R' R C C R'
H H
3. Preparation of Alkanes via Reduction
Alkyl halide reduction via lithium
aluminum hydride
Alkyl halide reduction via zinc / acid
H H H
+
LiAlH 4 Zn/H
R C R' R C R' R C R'
ether
X H X
4. Formation / Destruction of
Grignard reagents
Mg
R C X R C Mg X
ether
an alkyl halide a Grignard reagent
R C Mg X R C H + Mg(OH)X
H2 O
alkane
5. Coupling Reactions
Wurtz reaction
2R C X Na R C C R + 2NaX
a symmetrical
alkane
6. Coupling Reactions
Corey-House coupling (Gilman
Li
reagent)
R X R Li + LiX
CuX R
2R Li Cu Li + LiX
R
an organocuprate
(Gilman reagent)
R
Cu Li + R' X R R' + R Cu + LiX
R
7. Halogenation of Alkanes
Selectivity / Reactivity
F2
Case I: CH3 CH2 CH3 FCH2 CH2 CH3 + CH3 CH(F)CH3
u.v.
o 75% 25%
25 C
Cl2
Case II: CH3 CH2 CH3 ClCH2 CH2 CH3 + CH3 CH(Cl)CH3
u.v.
o 45% 55%
25 C
Br 2
Case III: CH3 CH2 CH3 BrCH2 CH2 CH3 + CH3 CH(Br)CH3
u.v.
o 3% 97%
125 C
