Table 2.
entry | substrate | heterocycle | yield [%][a] | ee [%][b] |
---|---|---|---|---|
1 |
(Z)-1g |
3g |
95 | Š5 |
2 | (R = Me) | 94 | 90 | |
3 | [R-R = –(CH2)5–] | 95 | 94 | |
4 | 89 | 62 | ||
5 |
4 (R = Ph) |
5 |
87[c] | 90/92 |
6 | (R = i-Pr) | 98[c] | 85/91 | |
7 | 87[c] | 88/90 | ||
8 | 69 | 77 | ||
9[d] | (R1 = Fmoc, R2 = Boc) | 86 | 94 | |
10[d] | (R1 = Fmoc, R2 = Ts) | 99 | 92 | |
11[d] | (R1 = Boc, R2 = Fmoc) | 99 | 91 |
Isolated yield.
Determined by HPLC analysis on chiral support.
Diastereomeric ratio = ~1:1.
Reaction run at 50 °C.