Table 1 Reaction optimizationa.

From: Dearomative 1,4-difunctionalization of naphthalenes via palladium-catalyzed tandem Heck/Suzuki coupling reaction

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Entry

Ligand

Base

Solvent

Yield of 3a (%)b

Yield of 4 (%)b

Yield of 5 (%)b

Yield of 6 (%)b

Yield of 7 (%)b

1

Ph3P

K2CO3

Toluene

2

90

4

–

–

2

Cy3P

K2CO3

Toluene

7

91

–

–

–

3

(EtO)3P

K2CO3

Toluene

5

89

–

–

–

4

L1

K2CO3

Toluene

16

61

7

–

–

5

L2

K2CO3

Toluene

18

76

–

–

–

6

L3

K2CO3

Toluene

24

54

6

–

–

7

L4

K2CO3

Toluene

46

40

3

3

–

8

L5

K2CO3

Toluene

42

52

–

–

–

9c

L5

Na2CO3

Toluene

18

–

–

–

–

10

L5

Cs2CO3

Toluene

–

43

52

–

–

11

L5

K3PO4

Toluene

21

66

–

10

–

12

L5

KF

Toluene

83

8

2

2

–

13

L5

CsF

Toluene

43

48

4

1

1

14

L4

KF

Toluene

71

21

–

3

–

15

L5

KF

THF

75

7

9

1

–

16

L5

KF

DME

72

9

11

2

–

17

L5

KF

MeCN

31

9

29

2

13

18

L5

KF

DMF

79

8

5

–

–

19d

L5

KF

Toluene

46

45

6

1

–

20e

L5

KF

Toluene

86 (79)

8

–

2

–

21e,f

L5

KF

Toluene

91 (83)

4

–

3

–

22e,f

L5

KF

Toluene

89

3

–

4

–

23e,f

L5

KF

Toluene

27

–

–

–

–

  1. THF tetrahydrofuran, DME 1,2-dimethoxyethane, DMF N,N-dimethylformamide.
  2. aReaction conditions: Amide 1 (0.2 mmol), 2a (0.4 mmol), Pd(dba)2 (0.01 mmol), ligand (0.02 mmol), base (0.5 mmol), solvent (2.0 mL), at 120 °C, 24 h. Full conversion of 1a unless otherwise noted (X = Br for entries 1–21; X = I for entry 22; X = Cl for entry 23).
  3. bDetermined by 1H NMR spectroscopy using MeNO2 as an internal standard; isolated yield in parenthesis.
  4. c23% conversion.
  5. dAt 100 °C.
  6. eAt 140 °C.
  7. f0.20 mmol of Ph4BNa and 16 h.
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