Table 2.
| |||
---|---|---|---|
entry | siloxane polymer | time |
1H-NMR resultsb (6 : 5 : 7) |
1 | 2 h | 100 : nd : <1c | |
2 | 2 h | 80 : nd : 20 | |
3 | 50 h | 1 : 99 : nd | |
4 | 20 h | 42 : 33 : 25 | |
5d | 20 h | 6 : 94 : nd | |
6 | 2 h | 83 : nd : 17 |
All reactions were performed on 0.3 mmol scale using 2.5 equiv PhLi, 3.0 equiv siloxane polymer, 3 mol % PdCl2, 4 mol % dpca, 10 mol % CuI.
Determined by 1H-NMR analysis of the reaction mixture following an aqueous workup, extraction with Et2O and polymer removal via precipitation in CH3CN.
98% yield of 6.
The insoluble polymer was stirred heterogeneously in reaction mixture. nd = not detected.