Table 1 Selected representative results of ligand screening

From: Non-C2 symmetric chiral ligand dictating allyl-allyl coupling

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entry

L*

Recovery of 1a (%)

Yield/eea of 3aa (%)

Yield of 4aa (%)/(Z:E)

Yield of 5aa/5aa’ (%)

1

(R)-L1

72

ND/-

21/(67:33)

12/8

2b

(S)-L2

53

ND/-

8/(75:25)

3/5

3

(R)-L3

93

ND/-

ND/-

ND/ND

4

(R,R)-L4

96

ND/-

ND/-

ND/ND

5

(R)-L5

64

5/-

trace/-

7/ND

6

(R)-L6

41

33/−24

4/(0:100)

13/13

7

(R,R)-L7

24

54/48

17/(76:24)

trace/trace

8

(R,R)-L8

27

28/−84

8/(100:0)

10/trace

9

(S,RP)-L9

53

18/−56

23/(83:17)

ND/ND

10

(R, RP)-L10

ND

97/72

4/(100:0)

2/ND

11

(R,SP)-L11

14

61/59

22/(86:14)

3/ND

12

(R, SP)-L12

31

59/81

5/(40:60)

ND/ND

13

(S)-L13

38

20/−54

27/(70:30)

2/3

14

(S)-L14

36

13/-50

33/(76:24)

ND/ND

15

(R)-L15

8

34/66

57/(72:28)

3/2

16

(R)-L16

ND

83/89

18/(50:50)

ND/ND

  1. Reaction conditions: 1a (0.2 mmol, 1.0 equiv.), 2a (1.5 equiv.), B2pin2 (1.5 equiv.), tBuOLi (1.5 equiv.) CuCl (5 mol%)/L* (6 mol%), [Pd(allyl)Cl]2 (2.5 mol%)/L* (6 mol%) THF (2.0 mL, 0.1 M), N2, r.t., 9 h. Yields and the recoveries were determined by 1H NMR analysis using CH3NO2 as the internal standard.
  2. ND not detected.
  3. aDetermined by HPLC after oxidation of 3aa with NaBO3•4H2O.
  4. bL* (12 mol%).
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