Table 1 Reaction conditions

From: Copper-catalyzed oxidative benzylic C-H cyclization via iminyl radical from intermolecular anion-radical redox relay

View full size image

Entrya

[cat](mol %)

Base

Solvent

3a(%)c

1

CuTC (10)

tBuOK

octane

48

2

Cu2O (10)

tBuOK

octane

62

3

CuO (10)

tBuOK

octane

68

4

CuCl (10)

tBuOK

octane

57

5

CuCl2 (10)

tBuOK

octane

63

6

CuSO4 (10)

tBuOK

octane

77

7

CuSO4 (10)

tBuONa

octane

0

8

CuSO4 (10)

KOH

octane

0

9

CuSO4 (10)

tBuOK

dioxane

70

10

CuSO4 (10)

tBuOK

toluene

45

11

CuSO4 (10)

tBuOK

DMF

22

12b

CuSO4 (10)

tBuOK

octane

81

13b, d

CuSO4 (2)

tBuOK

octane

85

14

Cu(300 mesh)

tBuOK

octane

54

15

none

tBuOK

octane

11

16

Pd2(dba)3 (5)

tBuOK

octane

0

17

Pd(PPh3)4 (10)

tBuOK

octane

17

18

Pd(OAc)2 (10)

tBuOK

octane

15

  1. aConditions: 1a (1 mmol), 2a (5 mmol), [cat] (x mol %), tBuOK (4 mmol), solvent (1 mL), 15 h, 90 °C, argon
  2. bOctane (0.75 mL)
  3. cDetermined by 1H NMR
  4. dBy column purification, 4.1 out of 5 equiv of nitriles 2a was recovered
Back to article page