Handbook of Functionalized Organometallics Applications in S

402
10 Functional Organonickel Reagents
N
N
SMe NiCl2(dppe), PhMgBr
>99%
Substitution of neopentyloxysulfonyl group by an aryl group is achieved by the
NiCl 2(dppf)-catalyzed cross-coupling reactions of biphenylsulfonates with an aryl
Grignard reagent. The reaction can be used for the synthesis of unsymmetrical
terphenyls [39].
O O
S
RO
Y
BrMg
NiCl 2(dppf)
Z
In the presence of a chiral ligand,Ni(COD) 2 serves as an active catalyst for the
asymmetric synthesis of chiral binaphthyls in excellent selectivity from
dinaphthothiophene. The remaining mercapto-moiety can be methylated and oxidized
to give the corresponding sulfoxides that can further react with MeMgI in
the presence of Ni(acac) 2 leading to the coupling products. A similar reaction for
the synthesis of axially chiral biaryls has been reported [40,41].
S
Me
Me
Ph
Ph
1. Ni(COD) 2/L*
RMgX
2. H + ,H2O S
S
Ph
SMe
O
N
N
Z
R
O
L* =
SH PPh2 N
Ni(acac) 2, MeMgI Ph
Me
76%
4-MeC6H4MgBr Ni(COD) 2,(S)-H-MOP
Me Tol
Me SH
MeMgI Ph Me
Ni(COD) 2,(S)-H-MOP Ph SH
Y