Nitric Acid → 3,3-dimethyl-6-nitrobenzo[c][1,2]oxaborol-1(3H)-ol

HRID 1425928Notes

Reaction equation

HRID 1425928 reaction equation
[N+:1]([O-:4])(O)=[O:2].[CH3:5][C:6]1([CH3:16])[O:10][B:9]([OH:11])[C:8]2[CH:12]=[CH:13][CH:14]=[CH:15][C:7]1=2>C(Cl)(Cl)(Cl)Cl>[CH3:5][C:6]1([CH3:16])[O:10][B:9]([OH:11])[C:8]2[CH:12]=[C:13]([N+:1]([O-:4])=[O:2])[CH:14]=[CH:15][C:7]1=2

Participants

4

Reactant 2

HCID 944Nitric AcidHCID 442289743,3-Dimethyl-1,3-dihydro-2,1-benzoxaborol-1-ol

Product 1

HCID 583730633,3-dimethyl-6-nitrobenzo[c][1,2]oxaborol-1(3H)-olYield 68%

Reagents, catalysts & solvents 1

HCID 5943Carbon TetrachlorideSolvent

Procedure

To 100% fuming nitric acid (10 mL) at −40° C. was added dropwise a solution of 3,3-dimethylbenzo[c][1,2]oxaborol-1(3H)-ol (XCVI) (1.37 g, 0.0085 mol) in carbon tetrachloride (40 mL), maintaining the temperature below −40° C. Stirring was continued for 20 min at −40° C. The yellow solution was poured onto ice and was stirred for 10 min at room temperature. The mixture was extracted with EtOAc. To the organic layer was added 1M aqueous NaOH to pH=7. The organic layer was separated, and washed with water, dried over MgSO4 and filtered, and the solvent was removed in vacuo to give an orange viscous oil. The oily residue was triturated with hexane to give pure 3,3-dimethyl-6-nitrobenzo[c][1,2]oxaborol-1(3H)-ol (XCVII) as a yellow solid (1.20 g, 5.8 mmol, yield 68%). 1H NMR (CDCl3) δ ppm 1.61 (s, 6H), 7.42 (s, 1H), 8.35 (d, J=8 Hz, 1H), 8.56 (d, J=8 Hz. 1H). ESIMS found for C9H10BNO4 m/z 206.3 (M−H).

Workup

  1. temperaturemaintaining the temperature below −40° C
  2. additionThe yellow solution was poured onto ice
  3. stirringwas stirred for 10 min at room temperature
  4. extractionThe mixture was extracted with EtOAc
  5. additionTo the organic layer was added 1M aqueous NaOH to pH=7
  6. customThe organic layer was separated
  7. washwashed with water
  8. dry with materialdried over MgSO4
  9. filtrationfiltered
  10. customthe solvent was removed in vacuo
  11. customto give an orange viscous oil
  12. customThe oily residue was triturated with hexane

Sources & evidence

ORD record
ord-1fec62a61605470d89d10a29ff8cd1bb
Source dataset
uspto-grants-2015_01
Patent number
US08933018B2

Reaction notes

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