Table 2. Reaction of 1 and 2a,b with TiCl4-Et3N (2:8).
entry | 1 | R1 | R2 | R3 | 2 | R4 | 5 | yield (%) |
---|---|---|---|---|---|---|---|---|
1 | 1a | H | H | H | 2a | Me | 5a | 40 |
2 | 1b | Me | H | H | 2a | Me | 5b | 45 |
3 | 1c | Cl | H | H | 2a | Me | 5c | 57 |
4 | 1d | H | Me | H | 2a | Me | 5d | 61 |
5 | 1e | H | Cl | H | 2a | Me | 5e | 46 |
6 | 1f | H | H | Cl | 2a | Me | 5f | 52 |
7 | 1g | H | F | H | 2a | Me | 5g | 53 |
8 | 1a | H | H | H | 2b | Et | 5h | 41 |
9 | 1i | 2a | Me | 5i | 41 |