Table 1 Reaction development and standard conditions

From: Enantioselective homologation of helical architectures from fluorenones to phenanthrenones with enhanced circular dichroism

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Entrya

Condition variation

C

A1

Yield (%)b

d.r.b

e.e. (%)c

Yield (%)b

e.e. (%)c

1

L3-PiMe2, B1′, 35 °C, DCM (0.05 M)

31 (C1′)

4.8:1

80/76

69

22

2

L3-PiEt2, B1′, 35 °C, DCM (0.05 M)

45 (C1′)

3.6:1

77/66

55

35

3

L3-PiiPr2, B1′,35 °C, DCM (0.05 M)

N.R.

-

-

100

0

4

NO-1, B1′, 35 °C, DCM (0.05 M)

20 (C1′)

5.0:1

80/73

80

15

5

NO-2, B1′, 35 °C, DCM (0.05 M)

27 (C1′)

6.8:1

83/45

83

24

6

NO-3, B1′, 35 °C, DCM (0.05 M)

31 (C1′)

7.0:1

91/70

69

32

7d

NO-3, B1′, 35 °C, DCM (0.025 M)

48 (C1′)

5.3:1

90/80

52

57

8d

NO-3, B1, 35 °C, DCM (0.025 M)

57 (C1)

5.2:1

95/91

43

87

9d

NO-3, B1, DCM (0.025 M)

29 (C1)

12.0:1

95/91

71

33

10d

NO-3, B1, TCE (0.025 M)

49 (C1)

8.7:1

98/93

51

80

11d,e

NO-3, B1, TCE (0.025 M), 8 h

55 (C1)

7.8:1

98/93

45

94

12d,e

NO-3, B1, TCE (0.025 M), 6 h

51 (C1)

8.3:1

98/91

49

82

13d,e

BINOL or BOX, B1, TCE (0.025 M)

N.R.

-

-

100

0

  1. aUnless otherwise noted, the reactions were carried out with A1 (0.05 mmol), diazo ester B (0.025 mmol), Sc(OTf)3/L* (1.3:1, 10 mol%) in solvent under air atmosphere for 12 h.
  2. bDetermined by 1H NMR, 0.05 mmol 1,1,2,2-tetrachloroethane was added as an internal standard.
  3. cDetermined by UPCC and HPLC.
  4. dWith diazo ester B (1.25 equiv.).
  5. eSc(OTf)3/L* was activated in THF for 30 min at 35 °C, then THF was evaporated.
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