Isobutyraldehyde → (R/S)-1-(2,6-dinitrophenyl)-2-methyl-1-propanol

Temperature

50 °C

To a solution of 1-iodo-2,6-dinitrobenzene (Smith and Ho, 1990), which is incorporated herein by reference) (1.55 g, 5.27 mmol) in anhydrous THF (18 mL) at minus 50° C. under a nitrogen atmosphere, phenylmagnesium bromide (2 M in THF, 3.2 mL, 6.4 mmol) was added dropwise at a rate such that the temperature would not exceed minus 45° C. Upon completion of the addition, the mixture was stirred at minus 50° C. for five min, followed by addition of isobutyraldehyde (0.96 mL, 11 mmol). The mixture was gradually warmed up to room temperature, quenched with saturated NH4Cl solution (10 mL), and then diluted with water (50 mL). The mixture was extracted with CH2Cl2 (100 mL) three times. The combined organic phase was washed with brine (50 mL), dried over Na2SO4, concentrated in vacuo, and the residue was purified by silica gel column chromatography to yield (R/S)-1-(2,6-dinitrophenyl)-2-methyl-1-propanol (0.375 g, 30%) as a yellow oil. 1H NMR (400 MHz, CDCl3): δ 7.82 (d, 2H, J=8.0 Hz, Ph-H), 7.59 (t, 1H, J=8.0 Hz, Ph-H), 4.83 (dd, 1H, J=9.2 and 7.6 Hz, Ph-CH), 2.87 (d, 1H, J=7.6 Hz, OH), 2.19 (m, 1H, CH), 1.12 (d, 3H, J=6.4 Hz, CH3), 0.76 (d, 3H, J=6.8 Hz, CH3).

1. custom50° C.
2. customexceed minus 45° C
3. additionUpon completion of the addition
4. temperatureThe mixture was gradually warmed up to room temperature
5. customquenched with saturated NH4Cl solution (10 mL)
6. additiondiluted with water (50 mL)
7. extractionThe mixture was extracted with CH2Cl2 (100 mL) three times
8. washThe combined organic phase was washed with brine (50 mL)
9. dry with materialdried over Na2SO4
10. concentrationconcentrated in vacuo
11. customthe residue was purified by silica gel column chromatography

ORD record

ord-a36552e01d8a453182a12c08fed7509e

Source dataset

uspto-grants-2016_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09399798B2