2-amino-4-methoxyphenol

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

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

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

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

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

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

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

Procedure: In a manner similar to that of Reference Example 16, 2-amino-4-methoxyphenol was allowed to react with 2,5-dibromovaleryl chloride, then cyclized to give 2-(3-bromopropyl)-6-methoxy-2H-1,4-benzoxazine-3(4H)-one as crystals. The yield was 56.9%. m.p. 102°-103° C. (recrystallization from ether).

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

Procedure: A mixture of 2-amino-4-methoxy-phenol (20.7 g, 0.15 mol), potassium O-ethylxanthate (26.2 g, 0.16 mol) and anhydrous pyridine was refluxed for two hours before it was cooled to room temperature and ice-cold 1N HCl (600 mL) was added. The precipitate was filtered, washed with water and dried in vacuo to give the title compound as a pale red solid (22.36 g): 1H NMR (CDCl3, 200 MHz): δ=7.20 (m, 1H), 6.78 (m, 2H), 3.82 (s, 3H). was refluxed for two hours before it The precipitate was filtered washed with water dried in vacuo

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

Procedure: A mixture of 4-methoxy-2-nitrophenol (30.2 g, 0.18 mol), 10% Pd/C, ethanol (200 mL), and ethyl acetate (200 mL) was hydrogenated at ambient pressure and temperature for three days before it was filtered and concentrated in vacuo to give the title compound as a dark brown solid (20.78 g): 1H NMR (CDCl3, 200 MHz): δ=6.64 (m, 1H), 6.32 (m, 1H), 6.21 (m, 1H), 3.71 (s, 3H). was filtered concentrated in vacuo

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

Procedure: 7B was treated with ethyl 2,3-dibromopropionate to form the ethyl ester of 6-methoxy-3,4-dihydro-2H-1,4-benzoxazine-2-carboxylic acid, and this was converted to 7, mp: 83°-85° C., by the procedures described in the other examples.

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

Procedure: 7B was treated with ethyl 2,3-dibromopropionate to form the ethyl ester of 6-methoxy-3,4-dihydro-2H-1,4-benzoxazine-2-carboxylic acid, and this was converted to 7, mp: 83°-85° C., by the procedures described in the other examples.

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

Procedure: 193.1 g of 7A was mixed with 1400 ml of water. 513 ml of ammonium hydroxide was added. 595 g of powdered sodium dithionite was added in portions over a period of 50 minutes. The resulting mixture was stirred for 2 hours. The solid product was collected and dried under vacuum over P2O5 to give 4-methoxy-2-aminophenol (7B), mp: 134°-136° C. The solid product was collected dried under vacuum over P2O5