1-(4-Bromo-2-nitro-phenoxy)-cyclopropanecarboxylic acid ethyl ester → 6-bromospiro[benzo[b][1,4]oxazine-2,1'-cyclopropan]-3(4H)-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Iron (1173 mg, 21 mmol) was added to a solution of ethyl 1-(4-bromo-2-nitrophenoxy)cyclopropanecarboxylate 7.20 (693 mg, 2.1 mmol) in acetic acid (10 mL) at room temperature. Mixture was heated at 60° C. for 5 hours. Mixture was cooled to rt, diluted with 100 mL ethyl acetate, and filtered over celite. Filtrate was concentrated under reduced pressure to yield 6-bromospiro[benzo[b][1,4]oxazine-2,1′-cyclopropan]-3(4H)-one 7.21 (523 mg), which was used in the next step without further purification.

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