Methanol → 2-(7-amino-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazin-4-yl)pyridine N-oxide

HRID 1197764Notes

Reaction equation

[CH3:1][C:2]1([CH3:22])[CH2:7][N:6]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][N+:9]=2[O-:14])[C:5]2[CH:15]=[CH:16][C:17]([N+:19]([O-])=O)=[CH:18][C:4]=2[O:3]1.[Cl-].[NH4+].CO>[Zn].O>[NH2:19][C:17]1[CH:16]=[CH:15][C:5]2[N:6]([C:8]3[CH:13]=[CH:12][CH:11]=[CH:10][N+:9]=3[O-:14])[CH2:7][C:2]([CH3:22])([CH3:1])[O:3][C:4]=2[CH:18]=1

Participants

Conditions

Temperature: 5 °C

Procedure

To a mixture of 8.05 g 2-(3,4-dihydro-2,2-dimethyl-7-nitro-2H-1,4-benzoxazin-4-yl)pyridine N-oxide, 28.50 g ammonium chloride, 140 ml methanol and 140 ml water, was added 34.94 g zinc powder under ice cooling, and the resulting mixture was stirred at 5° C. for 14 hours. The insoluble matters were filtered off from the reaction mixture, the filtrate was concentrated, the concentrate was extracted with ethyl acetate, the extract was dried over anhydrous magnesium sulfate, and the solvents were distilled off form the dried solution, giving 7.32 g of crude 2-(7-amino-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazin-4-yl)pyridine N-oxide.

Workup

filtrationThe insoluble matters were filtered off from the reaction mixture
concentrationthe filtrate was concentrated
extractionthe concentrate was extracted with ethyl acetate
dry with materialthe extract was dried over anhydrous magnesium sulfate
distillationthe solvents were distilled off form the dried solution

Sources & evidence

ORD record: ord-39aeb9a0820c44e2b4a55da533770a75
Source dataset: uspto-grants-1994_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05278158

Reaction notes

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