反应详情

Ethyl chloroformate (2 eq.) was added to a stirring solution of aniline 1 (1 eq.) and iPr2NEt (2 eq.) in dry THF (14 mL) at 0° C. The reaction was allowed to warm to rt over 2 h. The reaction concentrated and the resulting residue dissolved in EtOAc. The organic phase was washed with saturated aqueous NaHCO3 (3×) and the combined aqueous portions were extracted with EtOAc. The combined organic portions were concentrated to give an orange residue as 2. The residue was dissolved in DMF (20 mL), hydrazine monohydrate (1 eq.) added and the resulting reaction maintained at rt for 14 h. The reaction volume was reduced and the remaining solution was partitioned between EtOAc and water. The layers were separated and the aqueous phase extracted with EtOAc (3×). The combined organic layers were concentrated to give an orange solid as 3 which was carried forward without further purification: LCMS m/z 333.3 (MH+), tR=2.29 min.

1. concentrationThe reaction concentrated
2. dissolutionthe resulting residue dissolved in EtOAc
3. washThe organic phase was washed with saturated aqueous NaHCO3 (3×)
4. extractionthe combined aqueous portions were extracted with EtOAc
5. concentrationThe combined organic portions were concentrated
6. customto give an orange residue as 2
7. customthe resulting reaction
8. temperaturemaintained at rt for 14 h
9. customthe remaining solution was partitioned between EtOAc and water
10. customThe layers were separated
11. extractionthe aqueous phase extracted with EtOAc (3×)
12. concentrationThe combined organic layers were concentrated
13. customto give an orange solid as 3 which
14. customwas carried forward without further purification