Table 3.
entry | substrate | product(s) | yieldb(selectivity) | |
---|---|---|---|---|
1 | 9a, R = H | 10a, R = H | 11a, R = H | 72%(10a:11a = >20:1) |
2 | 9b, R = OMe | 10b, R = OMe | 11b, R = OMe | 74%(10b:11b = >20:1) |
3 | 9c, R = Cl | 10c, R = Cl | 11c, R = Cl | 71%(10c:11c = >20:1) |
4c | 9a, R = H | 10a, R = H | 11a, R = H | 56%(10a:11a = 1.2:1) |
5c |
12 |
13 |
38% | |
6c |
14 |
15 |
16 |
49%(15:16 = 2.5:1) |
Conditions. Substrate in DMF (0.1 M) was treated with Cu(EH)2 (3 equiv) and Cs2CO3 (1 equiv). The mixture was heated to 140 °C for 24 h in a pressure tube.
Yields refer to the sum of products isolated by chromatography on SiO2. The remainder of the material was either starting olefin or olefin-isomerized starting material.
Heated to 190 °C for 24 h.