Table 1.
Entry | Conditions | yield of 51 | yield of 53 |
---|---|---|---|
1 | CrCl2, cat. NiCl2, DMF, 60 °C | 10% (2:1 dr) | 17% |
2 | Nal, Sml2 THF/HMPA, −78 °C | 27% (2:1 dr) | 17% |
3 | Nal, Zn0, aq. NH4Cl, THF, rt | – | 51% |
4 | In0, Nal, DMF, 60 °C | 13% | – |
5 | Nal, SnCl2, DMF, 60 °Cb | 90% | – |
reactions performed on a 30 mg scale, isolated yields are shown.
yield on 7-gram scale