Methanol → 1,1-Dimethylethyl 2,3-dihydro-2-methyl-5-nitro-3-oxo-1H-indazole-1-carboxylate

HRID 2375928ノート

反応式

HRID 2375928 の反応式
[C:1]([O:5][C:6]([N:8]1[C:16]2[C:11](=[CH:12][C:13]([N+:17]([O-:19])=[O:18])=[CH:14][CH:15]=2)[C:10](=[O:20])[NH:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[C:21]1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.CO.CC(OC(/N=N/C(OC(C)C)=O)=O)C>CCOC(C)=O.C1COCC1>[C:1]([O:5][C:6]([N:8]1[C:16]2[C:11](=[CH:12][C:13]([N+:17]([O-:19])=[O:18])=[CH:14][CH:15]=2)[C:10](=[O:20])[N:9]1[CH3:21])=[O:7])([CH3:4])([CH3:2])[CH3:3]

参加物

7

反応物 4

HCID 887MethanolHCID 11776TriphenylphosphineHCID 5363146Diisopropyl azodicarboxylateHCID 59854581HCID 59854581、化合物

生成物 1

HCID 692755581,1-Dimethylethyl 2,3-dihydro-2-methyl-5-nitro-3-oxo-1H-indazole-1-carboxylate

試薬・触媒・溶媒 2

HCID 8028Tetrahydrofuran溶媒HCID 8857Ethyl Acetate溶媒

反応条件

温度
0 °C

実験手順

To a pre-dried flask were added 5-nitro-3-oxo-2,3-dihydroindazole-1-carboxylic acid tert-butyl ester (0.65 g, 2.33 mmol), triphenylphosphine (0.92 g, 3.50 mmol), methanol (115 μL, 2.80 mmol) and anhydrous THF (10 mL). The flask was evacuated and purged with N2 then cooled to 0° C. and diisopropylazodicarboxylate (690 μL, 3.50 mmol) added dropwise over 5 min. The mixture was stirred at rt overnight then diluted with EtOAc and partitioned over water. The organic layer was washed with brine, dried (MgSO4), filtered and concentrated. Purification by column chromatography on silica gel (Jones, 50 g) loading and eluting in DCM revealed the title compound as a white powder. 1H NMR (400 MHz, CDCl3): δ=1.68 (s, 9H), 4.21 (s, 3H), 8.10 (d, J=8.8 Hz, 1H), 8.39 (dd, J=9.2 Hz, 2.4 Hz, 1H), 8.61 (d, J=2.0 Hz, 1H). MS (ES+): m/z 294.3 (20) [MH+]. The N-alkylation product methyl-5-nitro-3-oxo-2,3-dihydroindazole-1-carboxylic acid tert-butyl ester was also isolated. 1H NMR (400 MHz, CDCl3): δ=1.68 (s, 9H), 3.69 (s, 3H), 8.02 (d, J=9.2 Hz, 1H), 8.48 (dd, J=9.2, 2.4 Hz, 1H), 8.77 (d, J=2.0 Hz, 1H).

後処理

  1. customThe flask was evacuated
  2. custompurged with N2
  3. custompartitioned over water
  4. washThe organic layer was washed with brine
  5. dry with materialdried (MgSO4)
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customPurification by column chromatography on silica gel (Jones, 50 g) loading
  9. washeluting in DCM

出典と根拠

ORDレコード
ord-01273cde179747b98184ee65c63c8f2a
出典データセット
uspto-grants-2008_12
特許番号
US07465726B2

反応ノート

読み込み中…