ethyl 3-amino-1-benzofuran-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 4.2 g (20.0 mmol) of ethyl 3-amino -2-benzo[b]furancarboxylate (EP 187487 A1) in 10 mL of N,N-dimethylformamide dimethyl acetal is heated at reflux temperature for 1.5 hours, then cooled to room temperature and concentrated in vacuo. The residue is partitioned between ethyl acetate and water. The organic layer is washed with water, dried over sodium sulfate, passed through a pad of diatomaceous earth and concentrated in vacuo. The solid is collected by filtration to provide 3.90 g (75%) of a white solid, mp 89-90° C. is heated at reflux temperature for 1.5 hours concentrated in vacuo The residue is partitioned between ethyl acetate and water The organic layer is washed with water dried over sodium sulfate concentrated in vacuo The solid is collected by filtration

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 4.2 g (20.0 mmol) of ethyl 3-amino-2-benzo[b]furancarboxylate (EP 187487 A1) in 10 mL of N,N-dimethylformamide dimethyl acetal is heated at reflux temperature for 1.5 hours, then cooled to room temperature and concentrated in vacuo. The residue is partitioned between ethyl acetate and water. The organic layer is washed with water, dried over sodium sulfate, passed through a pad of diatomaceous earth and concentrated in vacuo. The solid is collected by filtration to provide 3.90 g (75%) of a white solid, mp 89–90° C.; is heated at reflux temperature for 1.5 hours concentrated in vacuo The residue is partitioned between ethyl acetate and water The organic layer is washed with water dried over sodium sulfate concentrated in vacuo The solid is collected by filtration

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 4.2 g (20.0 mmol) of ethyl 3-amino -2-benzo[b]furancarboxylate (EP 187487 A1) in 10 mL of N,N-dimethylformamide dimethyl acetal is heated at reflux temperature for 1.5 hours, then cooled to room temperature and concentrated in vacuo. The residue is partitioned between ethyl acetate and water. The organic layer is washed with water, dried over sodium sulfate, passed through a pad of diatomaceous earth and concentrated in vacuo. The solid is collected by filtration to provide 3.90 g (75%) of a white solid, mp 89-90° C. is heated at reflux temperature for 1.5 hours concentrated in vacuo The residue is partitioned between ethyl acetate and water The organic layer is washed with water dried over sodium sulfate concentrated in vacuo The solid is collected by filtration