15
homo- coupling of (trimethylstannyl) alkynes was achieved by employing (E)-1,2diiodoethene as effective oxidant (Scheme 2.10) [41].
Iron-catalyzed homo-coupling of arylmagnesium reagents was successfully
developed using 1,2-dichloroethane as the oxidant (Scheme  2.11) [42]. Various
arylmagnesium reagents were efficiently converted into the corresponding symmetrical biaryls in the presence of simple FeCl 3 as catalyst precursor. Meanwhile, a
similar iron-catalyzed homo-coupling of simple and functionalized arylmagnesium
reagents using 1,2-dihalogenoethanes as the oxidant was reported (Scheme  2.12)
RSnBu 3
PdCl 2 (10 mol%)
As 3 Ph (10 mol%)
ClCH 2 CH 2 Cl, DCE, r.t.,17 h
R R
R = Aryl, Alkenyl, Alkynyl
Scheme 2.8 Pd-catalyzed
oxidative homo-coupling
of organostannanes
ArSnBu 3
ArB(OH) 2
Ar 2 SiF 2
PdCl 2 (MeCN) 2 (5 mol%)
TMEDA (5 mol%)
Ph-ACDB, DMI, 100 o C, 2 h
Ar Ar
PdCl 2 (dppb) 2 (5 mol%)
Ph-ACDB, K 2 CO 3
THF/H 2 O, 70 o C, 24 h
Ar Ar
PdCl 2 (PEt 3 ) 2 (3.3 mol%)
CuI (3.3 mol%)
Me 2 -ACDB, KF
THF, reflux, 48 h
Ar Ar
Br
CO 2 Et
Br
Me
Me
Br
CO 2 Et
Br
Ph
Ph-ACDB
Me 2 -ACDB
Scheme 2.9 Pd-catalyzed oxidative homo-coupling of arylstannanes, arylboronic acids, and
arylfluorosilanes
arylfluorosilanes
R
SnMe 3
(SiPy)PdCl 2 (2 mol%)
(E)-1,2-diiodoethene
CD 3 CN/CDCl 3 , r.t.
R
R
I
I
Si
N
N
Me
Me
SiPy
(E)-1,2-diiodoethene
Scheme 2.10 Pd-catalyzed
oxidative homo-coupling of
(trimethylstannyl)alkynes
ArMgBr
FeCl 3 (1-5 mol%)
ClCH 2 CH 2 Cl, Et 2 O, reflux, 1-12 h
Ar Ar
Scheme 2.11 Fe-catalyzed
oxidative homo-coupling
of arylmagnesium reagents
2 Transition Metal-Catalyzed Oxidative Coupling Involving Two Organometallic…