Table 1. Dehydrogenative Coupling of 1,4-Benzenedimethanol with Diphenylsilanea.
| entry | solventb | temp. | condition | t (h) | conv% | Mn (g/mol)c | Mw/Mnc |
|---|---|---|---|---|---|---|---|
| 1 | CD3CN | reflux (81 °C) | under N2 | 12 | >95 | 4000 | 1.28 |
| 2 | THF | reflux (66 °C) | under N2 | 12 | 50 | 1900 | 1.36 |
| 3d | 1,4-dioxane | reflux (101 °C) | under N2 | 20 | >95 | 7900 | 1.57 |
| 4e | toluene | reflux (110 °C) | under N2 | 12 | >95 | 9200 | 1.66 |
| 5 | toluene | 25 °C | under N2 | 48 | 0 | ||
| 6f | xylenes | reflux (143 °C) | under N2 | 12 | >95 | 6000 | 1.14 |
| 7 | mesitylene | reflux (165 °C) | under N2 | 12 | >95 | 7200 | 1.23 |
| 8 | toluene | reflux (110 °C) | under air | 48 | 58 | 4500 | 1.15 |
a
Reaction conditions: substrate, 0.8–0.9 mmol; silane, 1.0 equiv; and Mn catalyst 1, 1.0 mol %.
b
Solvent used was 2.4–2.8 mL.
c
Determined by GPC calibrated with polystyrene standard.
d
Isolated yield 75.9%.
e
Isolated yield 75.6%.
f
Isolated yield 70%.