Trimethylsilyldiazomethane → Methyl 2-fluoro-6-nitrobenzoate

HRID 132250Notes

Reaction equation

HRID 132250 reaction equation
[F:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]([N+:11]([O-:13])=[O:12])[C:3]=1[C:4]([OH:6])=[O:5].[Si](C=[N+]=[N-])(C)(C)[CH3:15]>CO.C(#N)C>[F:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]([N+:11]([O-:13])=[O:12])[C:3]=1[C:4]([O:6][CH3:15])=[O:5]

Participants

4

Reactant 2

HCID 167693TrimethylsilyldiazomethaneHCID 6037582-Fluoro-6-nitrobenzoic acid

Product 1

HCID 597752Methyl 2-fluoro-6-nitrobenzoateYield 94%

Reagents, catalysts & solvents 1

HCID 21959252Acetonitrile methanolSolvent

Procedure

To 2-fluoro-6-nitrobenzoic acid (712 mg, 3.85 mmol) in methanol/acetonitrile (10 mL/10 mL) was dropwise added TMSCHN2 at 0° C. under N2 until yellow color persistent, and stirred additional 30 min. Then the reaction was quenched with HOAcat 0° C. until the yellow color disappears. Partial of the solvent was removed o rotary vacuum, the residue was dissolved in small amount of EtOAc, purified on flash chromatography eluting with 30˜50% EtOAc/hexanes (600 mL) to afford the expected product, methyl 2-fluoro-6-nitrobenzoate, (716 mg, 94% yield) which was used in step-2; 1H NMR (400 MHz, CDCl3) δ ppm 3.96 (s, 3 H), 7.40-7.48 (m, 1 H), 7.58 (td, J=8.31, 5.54 Hz, 1 H), 7.94 (d, J=8.31 Hz, 1 H); Mass spec. 200.05 (MH+), Calc. for C8H6FNO4 199.03.

Workup

  1. customat 0° C.
  2. customThen the reaction was quenched with HOAcat 0° C. until the yellow color
  3. customPartial of the solvent was removed o rotary vacuum
  4. dissolutionthe residue was dissolved in small amount of EtOAc
  5. custompurified on flash chromatography
  6. washeluting with 30˜50% EtOAc/hexanes (600 mL)

Sources & evidence

ORD record
ord-6c16361fbf9145fdac97506d78b26b61
Source dataset
uspto-grants-2008_06
Patent number
US07384930B2

Reaction notes

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