Hydrochloric Acid → 1-(2-ethoxyethyl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

HRID 334253Notes

Reaction equation

HRID 334253 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.C(OCN1C2N=CN=C(C3C=NN([CH:37]([O:39][CH2:40][CH3:41])[CH3:38])C=3)C=2C=C1)(=O)C(C)(C)C.Cl.C([O-])(O)=O.[Na+]>O1CCOCC1.C1(C)C=CC=CC=1>[CH2:37]([O:39][CH2:40][CH2:41][N:12]1[CH:13]=[C:9]([B:4]2[O:5][C:6]([CH3:7])([CH3:8])[C:2]([CH3:14])([CH3:1])[O:3]2)[CH:10]=[N:11]1)[CH3:38]

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 516892Sodium BicarbonateHCID 27740104-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazoleHCID 57868870(4-(1-(1-Ethoxyethyl)-1H-pyrazol-4-yl)-7H-pyrrolo[2,3-d]pyrimidin-7-yl)methyl pivalate

Product 1

HCID 684741121-(2-ethoxyethyl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazoleYield 97.3%

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 312751,4-DioxaneSolvent

Conditions

Temperature
37.5 °C

Procedure

A 22 L 4-neck flask equipped with a mechanical stirrer, thermowell, addition funnel, condenser and N2 inlet was charged with 4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)-1H-pyrazole (17, 1.42 kg, 7.32 mol), toluene (9.5 L) and ethyl vinyl ether (18, 790.5 g, 1050 mL, 10.98 mol, 1.50 equiv). A 4 M HCl in dioxane (50 mL) was added via an addition funnel over 10 minutes and the resulting reaction mixture was heated at 35-40° C. for 7 hr to give a clear homogeneous solution. When the reaction was shown to be complete by GC, solid NaHCO3 (130 g) was added and the mixture was stirred for 1 hr before being filtered. The filtrate was concentrated under reduced pressure. Heptane (200 mL) was added to the residue to affect crystallization. The solid was collected by filtration and dried in a vacuum oven to afford 1-(ethoxyethyl)-4-(4,4,5,5-tetramethyl[1,3,2]dioxaborolan-2-yl)-1H-pyrazole (19, 1.896 Kg, 1.948 Kg theoretical, 97.3%) as a white to off-white solid. For 19: 1H NMR (DMSO-d6, 400 MHz) δ ppm 8.09 (s, 1H), 8.58 (s, 1H), 7.62 (s, 1H), 5.55 (q, 1H, J=6.1 Hz), 3.37 (dq, 1H, J=7.1, 9.6 Hz), 3.12 (dq, 1H, J=7.0, 9.7 Hz), 1.56 (d, 3H, J=6.0 Hz), 1.24 (s, 12H), 1.00 (t, 3H, J=7.0 Hz); C13H23BN2O3 (MW, 266.14), LCMS (EI) m/e 267 (M++H).

Workup

  1. customA 22 L 4-neck flask equipped with a mechanical stirrer
  2. additionthermowell, addition funnel, condenser and N2 inlet
  3. customthe resulting reaction mixture
  4. customto give a clear homogeneous solution
  5. additionwas added
  6. filtrationbefore being filtered
  7. concentrationThe filtrate was concentrated under reduced pressure
  8. additionHeptane (200 mL) was added to the residue
  9. customcrystallization
  10. filtrationThe solid was collected by filtration
  11. customdried in a vacuum oven

Sources & evidence

ORD record
ord-ff6632a3db6f496bac71745253f7dbf8
Source dataset
uspto-grants-2014_11
Patent number
US08883806B2

Reaction notes

Loading…