Nitrogen → 5-(3-Nitro-pyrazol-1-ylmethyl)-furan-2-carbaldehyde

HRID 2064925Notes

Reaction equation

N#N.[N+:3]([C:6]1[CH:10]=[CH:9][N:8]([CH2:11][C:12]2[O:16][C:15]([CH:17]=[O:18])=[CH:14][CH:13]=2)[N:7]=1)([O-:5])=[O:4].[CH3:19][Mg]Br>C1COCC1.[NH4+].[Cl-]>[N+:3]([C:6]1[CH:10]=[CH:9][N:8]([CH2:11][C:12]2[O:16][C:15]([CH:17]([OH:18])[CH3:19])=[CH:14][CH:13]=2)[N:7]=1)([O-:5])=[O:4].[N+:3]([C:6]1[CH:10]=[CH:9][N:8]([CH2:11][C:12]2[O:16][C:15]([CH:17]=[O:18])=[CH:14][CH:13]=2)[N:7]=1)([O-:5])=[O:4]

Participants

Conditions

Temperature: -78 °C

Procedure

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of 5-(3-nitro-pyrazol-1-ylmethyl)-furan-2-carbaldehyde (10.50 g, 47.47 mmol) in THF (479.2 mL) was treated at −78° C. with methylmagnesium bromide (47.47 mL of a 1M solution in THF, 47.47 mmol). The reaction mixture was stirred at −78° C. for 4 h. It was then poured in sat. aq. NH4Cl (450 mL). The aq. phase was extracted with EA (2×500 mL) and the combined org. extracts were dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (50:50 hept-EA) gave the title compound as a mixture with 5-(3-nitro-pyrazol-1-ylmethyl)-furan-2-carbaldehyde. TLC: rf (50:50 hept-EA)=0.24. LC-MS-conditions 02: tR=0.78 min. 1H NMR (400 MHz, CDCl3) characteristic signals 81.53 (d, J=6.5 Hz, 3H), 2.15-2.24 (m, 1H), 4.81-4.91 (m, 1H), 5.35 (s, 2H), 6.24 (d, J=3.0 Hz, 1H), 6.43 (d, J=3.3 Hz, 1H), 6.89 (d, J=2.3 Hz, 1H), 7.49 (d, J=2.5 Hz, 1H).

Workup

extractionThe aq. phase was extracted with EA (2×500 mL)
dry with materialextracts were dried over MgSO4
filtrationfiltered
customthe solvents were removed under reduced pressure
customPurification of the residue by FC (50:50 hept-EA)

Sources & evidence

ORD record: ord-c81f6aaf3ff64a9a9586ee425df96a05
Source dataset: uspto-grants-2012_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08288419B2

Reaction notes

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