反应详情

Using an analogous reaction procedure and workup as described in example 1 for the preparation of intermediate I-1d above, ethyl 3,4-difluorophenethylcarbamate (I-49c: 5 g, 21.8340 mmol) in POCl3 (43.6 mL) was reacted with P2O5 (6.19 g, 43.6681 mmol) at 110° C. for 2 hours to afford the crude product. Purification by column chromatography on silica gel (50% ethyl acetate in hexane) afforded 800 mg of the product (18.91% yield).

1. customan analogous reaction procedure
2. customworkup as described in example 1 for the preparation of intermediate I-1d above
3. customto afford the crude product
4. customPurification by column chromatography on silica gel (50% ethyl acetate in hexane)