Tetrabutylammonium Fluoride → (S)-4-(3-Hydroxy-2-methylpropyl)-6-methyl-4H-benzo[1,4]oxazin-3-one

HRID 2102541Notes

Reaction equation

HRID 2102541 reaction equation
[Si]([O:8][CH2:9][C@@H:10]([CH3:24])[CH2:11][N:12]1[C:17]2[CH:18]=[C:19]([CH3:22])[CH:20]=[CH:21][C:16]=2[O:15][CH2:14][C:13]1=[O:23])(C(C)(C)C)(C)C.CCCC[N+](CCCC)(CCCC)CCCC.[F-]>C1COCC1>[OH:8][CH2:9][C@@H:10]([CH3:24])[CH2:11][N:12]1[C:17]2[CH:18]=[C:19]([CH3:22])[CH:20]=[CH:21][C:16]=2[O:15][CH2:14][C:13]1=[O:23]

Participants

4

Procedure

The compound (S)-4-[3-(tert-butyldimethylsilanyloxy)-2-methylpropyl]-6-methyl-4H-benzo[1,4]oxazin-3-one (101IS60-1) (1.0 g, 2.9 mmol) was dissolved in dry THF (12 mL) and TBAF (1.2 g, 3.8 mmol) was added. The reaction was stirred at rt overnight and the solution was concentrated under reduced pressure, the remaining oil was diluted with EtOAc (60 mL) and washed with brine (3×30 mL), dried (Na2SO4) filtered and concentrated under reduced pressure. The remaining oil was purified by flash chromatography (SiO2; Heptane/EtOAc 30:70) to yield an oil which crystallized upon standing (0.69 g, 76%). 1H NMR (CDCl3) δ 6.88 (d, J=8.4 Hz, 1H), 6.83-6.78 (m, 2H), 4.59 (brs 2H), 4.22 (dd J=10.0, 14.4 Hz), 3.57-3.38 (m, 3H), 2.9 (vbrs, 1H), 2.33 (s, 3H), 2.04 (m, 1H), 1.08 (d, J=7.2 Hz); 13C NMR (CDCl3) δ 165.7, 143.4, 132.3, 124.9, 117.1, 115.9, 67.6, 63.7, 43.5, 34.2, 21.3, 15.1.

Workup

  1. concentrationthe solution was concentrated under reduced pressure
  2. additionthe remaining oil was diluted with EtOAc (60 mL)
  3. washwashed with brine (3×30 mL)
  4. dry with materialdried (Na2SO4)
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure
  7. customThe remaining oil was purified by flash chromatography (SiO2; Heptane/EtOAc 30:70)
  8. customto yield an oil which
  9. customcrystallized

Sources & evidence

ORD record
ord-562091158a0c4bde805ffe525ac91a92
Source dataset
uspto-grants-2009_08
Patent number
US07576078B2

Reaction notes

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