Dimethylformamide → 4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole

HRID 44960

Reaction equation

HRID 44960 reaction equation
[CH3:1][C:2]1([CH3:14])[C:6]([CH3:8])([CH3:7])[O:5][B:4]([C:9]2[CH:10]=[N:11][NH:12][CH:13]=2)[O:3]1.[CH3:15]N(C=O)C.[H-].[Na+].[CH3:22][SiH:23]([CH3:29])[CH2:24][CH2:25][O:26][CH2:27]Cl>>[CH3:1][C:2]1([CH3:14])[C:6]([CH3:7])([CH3:8])[O:5][B:4]([C:9]2[CH:13]=[N:12][N:11]([CH2:27][O:26][CH2:25][CH2:24][Si:23]([CH3:29])([CH3:15])[CH3:22])[CH:10]=2)[O:3]1

Participants

5

Conditions

Temperature
0 °C

Procedure

A solution of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (2.0 g, 0.010 mol) and DMF (30.0 mL, 0.387 mol) was cooled to 0° C. Sodium hydride (320 mg, 0.013 mol) (60% in oil) was added and the mixture was stirred for 10 min. [β-(dimethylsilyl)ethoxy]methyl chloride (2.4 mL, 0.013 mol) was added and the resulting mixture was stirred for 20 min at 0° C. and 2 h at room temperature. The reaction was partitioned between water and ethyl acetate. The organic layer was washed with brine, dried over MgSO4 and concentrated to give 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-[2-(trimethylsilyl)ethoxy]methyl-1H-pyrazole as a crude material. LC/MS (M+H)+: 325, 1H NMR (CDCl3) δ 7.85 (s, 1H), 7.80 (s, 1H), 5.45 (s, 2H), 3.55 (t, 2H), 1.35 (s, 12H), 0.95 (t, 2H), 0.0 (s, 9H).

Workup

  1. additionwas added
  2. customThe reaction was partitioned between water and ethyl acetate
  3. washThe organic layer was washed with brine
  4. dry with materialdried over MgSO4
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-5afcaf14c94c4e1090edf383da608338
Source dataset
uspto-grants-2013_09
Patent number
US08541425B2

Linked notes

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