Table 2.
Synthesis of (α-fluoro)vinyl sulfides via thiodesulfonylation of (α-fluoro)vinyl sulfones.
| Entry | Sulfone | Methoda | Productb (E/Z)c | Yieldd |
|---|---|---|---|---|
| 1 | 3a (96:4) | A | 8a (92:8) | 92 |
| 2 | 3a (96:4) | B | 8a (94:6) | 65e |
| 3 | 3a (94:4) | A | 10a (83:17) | 50 |
| 4 | 3b (86:14) | A | 8b (93:7) | 82, 62f |
| 5 | 3b (86:14) | B | 8b (92:8) | 56 |
| 6 | 3b (86:14) | C | 8b (92:8) | 92 f |
| 7 | 3b (86:14) | C | 9b (92:8) | 90 |
| 8 | 3b (86:14) | C | 11b (94:6) | 69 f |
| 9 | 3c (90:10) | B | 8c (93:7) | 60f, 72 |
| 10 | 3d (97:3) | B | 8d (93:7) | 73 |
| 11 | 3e (88:12) | B | 8e (70:30) | 10g |
| 12 | 3f (84:16) | C | 8f (70:30) | 12h |
| 13 | 3g | B | 8g | 65 |
| 14 | 3h (57:43) | B | 8h (50:50) | 58 |
| 15 | 3h (57:43) | C | 8h (50:50) | 68 |
| 16 | 3h (100:0) | C | 8h (50:50) | 85 |
| 17 | 3h (0:100) | C | 8h (33:67) | 70 |
| 18 | 3h (100:0) | C | 9h (64:36) | 96 |
| 19 | 3h (57:43) | B | 9h (50:50) | 59 |
| 20 | 3h (57:43) | C | 11h (55:45) | 42 |
a
Method A: thiol/ACCN/toluene/110 °C/6 h; Method B: thiol/ACCN/H2O/100 °C/6 h; Method C: thiol/ACCN/MeOH/65 °C/5 h.
b
Reactions were performed on 0.1–0.5 mmol scale of sulfones (0.05 mM) with 1.25–2.0 equiv. of thiols and 0.25–0.50 equiv. of ACCN or AIBN.
c
Determined by GC-MS and 1H or 19F NMR.
d
Isolated yield.
e
Reaction with phenyl disulfide gave 8a (55%, Methods B or C).
f
AIBN instead of ACCN.
g
83% based on Z-3e.
h
75% based on Z-3f.