Table 1 Suzuki–Miyaura cross-coupling of 15a and 16aa

From: Total synthesis of cyrneines A–B and glaucopine C

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Entry

Catalyst (5 mol%)

Base (equiv)

Solvent

T (oC)

Yield (%)b

1

PdCl2(dppf)

K2CO3

DMSO

85

21

2

Pd(PPh3)4

K2CO3

dioxane

85

34

3

Pd(PPh3)4

K3PO4

dioxane

85

44

4

Pd(OAc)2/dppp

K2CO3

dioxane

85

33

5

Pd(OAc)2/dppb

K2CO3

dioxane

85

41

6

PdCl2/dppp

K2CO3

dioxane

85

22

7

Pd(OAc)2/dppb

K3PO4

dioxane

85

61

8

18

K2CO3

DMF/EtOH (v/v = 1:1)

rt

>99c

9

18

K2CO3

DMF/EtOH (v/v = 1:1)

rt

95d

  1. aReaction conditions: 15a (47.0 mg, 0.1 mmol), 16a (27.6 mg, 0.2 mmol), catalyst (5 mol%), and base (3.0 equiv), in 1 mL solvent under nitrogen atmosphere for 12 h
  2. bIsolated yield
  3. cThe reaction was run at rt for 5 h
  4. dThe reaction was performed with 6.6 g of 15a and was quenched until 15a had disappeared as monitored by TLC