Table 1 Optimization of the reaction conditions

From: Copper-catalysed asymmetric annulation of yne-allylic esters with amines to access axially chiral arylpyrroles

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Entry

1

L

T (°C)

t (h)

Yield of 3a (%)b

er (%)c

1

1a

L1

60

12

8

52:48

2

1a

L2

60

12

14

47:53

3

1a

L3

60

12

28

67:33

4

1a

L4

60

12

49

77:23

5

1a

L5

60

12

65

80:20

6

1a

L6

60

12

58

82.5:17.5

7

1a

L7

60

12

69

83:17

8

1a

L8

60

24

65

81:19

9

1a

L7

25

72

80

87:13

10

1b

L7

25

1.5

83

88.5:11.5

11

1b

L7

0

2

87

93:7

12

1b

L7

−10

5

84

93.5:6.5

13d

1b

L7

−10

5

77

95:5

14e

1b

L7

−10

5

61

92.5:7.5

15 f

1b

L7

−10

17

98

97.5:2.5

  1. a Reaction conditions: 1 (0.15 mmol), 2a (2.0 equiv., 0.3 mmol), MeOH (0.15 M), DIPEA (1.5 equiv., 0.225 mmol), Cu(CH3CN)4BF4 (10 mol%), L (12 mol%), N2. b Isolated yield of 3a. c The enantiomeric ratio of 3a was determined by HPLC using a chiral stationary phase. d Et3N was used. e K2CO3 was used. f Without base. The PMP is p-methoxyphenyl.
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