Table 1 Optimization of reaction conditions and control experiments.a

From: Cobalt-catalyzed hydrothiolation of alkynes for the diverse synthesis of branched alkenyl sulfides

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Entry

Variation

Yield of 3a (%)b

b/l b

1

None

90

97/3

2c

PhthN-SMe instead of TsSMe

5

–

3c

MeSSMe instead of TsSMe

5

–

4c

MsSMe instead of TsSMe

15

94/6

5

L2 instead of L1

58

99/1

6

L3 instead of L1

16

84/16

7

L4 instead of L1

0

–

8

Ph2SiH2 instead of OMTS

86

96/4

9

PhSiH3 instead of OMTS

29

96/4

10

TMDSO instead of OMTS

67

96/4

11

NaOMe instead of LiOMe

4

–

12

LiOtBu instead of LiOMe

14

86/14

13

CsF instead of LiOMe

9

–

14c

45 °C

91

96/4

  1. aIn glove box, 1a (0.50 mmol), 2a (0.25 mmol), CoBr2 (5 mol%), L1 (6 mol%), OMTS (1,1,1,3,5,7,7,7-octamethyltetrasiloxane, 1.2 eq.), LiOMe (2.5 eq.), THF (2.0 mL), 40 °C for 12 h.
  2. bDetermined by 1H NMR using 1,1,2,2-tetrachloroethane as an internal standard.
  3. cL1•CoBr (5 mol%) was used instead of CoBr2 and L1.
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