Table 3.
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Entry | Heterocycle | Substrate [R] | mol % 2a | SN2′:SN2[b] | Yield [%][c] | e.r.[d] |
1 | 2-furyl | Ph | 0.5 | >98:2 | 93 | >98:2 |
2 | 2-furyl | oBrC6H4 | 0.5 | >98:2 | 86 | >98:2 |
3 | 2-furyl | oMeOC6H4 | 0.5 | >98:2 | 95 | >98:2 |
4 | 2-furyl | oMeC6H4 | 1.0 | >98:2 | 98 | 98:2 |
5 | 2-furyl | pNO2C6H4 | 0.5 | >98:2 | 96 | >98:2 |
6 | 2-furyl | SiMe2Ph | 1.0 | >98:2 | 91 | 86.5:13.5 |
7[e] | 3-furyl | Ph | 1.0 | >98:2 | 90 | 97:3 |
8 | 2-thienyl | Ph | 0.5 | >98:2 | 98 | 96:4 |
9 | 2-thienyl | oBrC6H4 | 1.5 | >98:2 | 98 | 98:2 |
10 | 2-thienyl | pNO2C6H4 | 0.5 | >98:2 | 96 | 94:6 |
11 | 2-thienyl | CO2tBu | 0.5 | >98:2 | 94 | 87.5:12.5 |
12[e] | 3-thienyl | Ph | 1.0 | >98:2 | 94 | 94:6 |
13[e] | 3-thienyl | oBrC6H4 | 1.0 | >98:2 | 89 | 97:3 |
14[e] | 3-thienyl | SiMe2Ph | 1.0 | >98:2 | 95 | 94:6 |
See Table 2.
The corresponding 3-bromofuran or 3-bromothiophene used as starting materials (treatment with nBuLi in Et2O); see the Supporting Information for experimental details.