Table 4 Optimization of asymmetric reaction

From: Radical asymmetric intramolecular α-cyclopropanation of aldehydes towards bicyclo[3.1.0]hexanes containing vicinal all-carbon quaternary stereocenters

Entry

Amine

Oxidant

T (°C)

Conversion (%)

era

1

A12

BI-OH

60

100

82.5:17.5

2

A12

BI-OH

30

80

85.5:14.5

3

A12

F-BI-OH

30

100

88:12

4

A12

F-BI-OH

20

85

91.5:8.5

5

A12

DF-BI-OH

20

100

90.5:9.5

6

A13

F-BI-OH

20

90

91:9

7

A14

F-BI-OH

20

90

90:10

8

A15

F-BI-OH

20

100

70:30

9b

A12

DF-BI-OH

10

50

92.5:7.5

10c

A12

DF-BI-OH

10

100

93:7

11 d

A14

DF-BI-OH

10

100

95:5

  1. Reactions were run on 0.05 mmol scale
  2. aDetermined by chiral stationary HPLC
  3. b96 h
  4. c20 mol% of n-Bu4NI was added and reaction time was 72 h
  5. d20 mol% of n-Bu4NI was added and 60% isolated yield of 2a after 72 h
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