Advances in C–C and C–X Coupling Using Palladium–NHeterocyclic Carbene (Pd–NHC) Complexes - New Trends in Cross-Coupling: Theory and Applications - page 198

Br

74a (1 mol%)

N N

+

R

K 3 PO 4, NMP
130°C, 20 - 24 h

S S

R

R=H:89%
R=OMe:78%
R=Me:85%

4

N

N

N

N

Pd

Br Br

74a

Scheme 4.51 Direct arylation of benzothiazole using 74a.

Cl

71 (1 mol%)

+

R''

R''

R R

N KOAc,DMA,150°C,20h N

R' R'

X=Cl,Br

NC

O

O

O

N N

N

CN MeO CN

36 - 87% 38 - 7 8% 27 - 83%

N N

Ph

CF 3 COMe

25 - 3 9% 55 - 86%

Scheme 4.52 Arylation of pyrroles using deactivated chlorides and 71.

[Pd(NHC)(PCy 3 )(OAc) 2 ](75)
(2.5 mol%) X

R'

+

R'

NN

KOAc,DMA,140°C
a) Conventional heating: 1 8h
b) Microwave: 2h

Ph

NN Ph

NN

R

X=Cl,Br

R

AcO Pd

OAc

PCy 3

N N

N

COMe CN

OMe

N N

N

[Pd(NHC)(PCy 3 )(OAc) 2 ]
75

a) X = Cl: 60%
b) X = Cl: 70%
a) X = Br : 66%
b) X = Br : 72%

a) X = Cl: 41%
b) X = Cl: 56%
a) X = Br: 4 5%
b) X = Br: 6 0%

a) X = Cl: 52%
b) X = Cl: 56%
a) X = Br: 5 3%
b) X = Br: 5 8%

Scheme 4.53 Direct arylation of imidazoles using [Pd(NHC)(PCy 3 )(OAc) 2 ](75).