Ethanol → 5-methoxy-2-(tetrahydro-2H-pyran-2-yl)-3(2H)-pyridazinone

HRID 54659Notes

Reaction equation

HRID 54659 reaction equation
Cl[C:2]1[C:3](=[O:16])[N:4]([CH:10]2[CH2:15][CH2:14][CH2:13][CH2:12][O:11]2)[N:5]=[CH:6][C:7]=1[O:8][CH3:9].C(O)C.C(N(CC)CC)C>O.[Pd]>[CH3:9][O:8][C:7]1[CH:6]=[N:5][N:4]([CH:10]2[CH2:15][CH2:14][CH2:13][CH2:12][O:11]2)[C:3](=[O:16])[CH:2]=1

Participants

6

Reactant 3

HCID 702EthanolHCID 8471TriethylamineHCID 106103354-Chloro-5-methoxy-2-(2-tetrahydropyranyl)pyridazin-3(2H)-one

Product 1

HCID 105603805-methoxy-2-(tetrahydro-2H-pyran-2-yl)-3(2H)-pyridazinoneYield 100%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 962WaterSolvent

Conditions

Temperature
43 °C

Procedure

4-Chloro-5-methoxy-2-(tetrahydro-2H-pyran-2-yl)-3(2H)-pyridazinone (2486 g, 10.16 moles), ethanol (8 L), triethylamine (2 L, 14.23 moles) and 5% Pd-C (100 g of 50% water-wet Pd-C) were added to a 5 gallon (18.9 L) autoclave. The mixture was hydrogenated at 50-60 psi (344-413 kilo Pascals) of H2 and heated to a maximum temperature of 43° C. After 24 h., the reaction was complete. The reaction mixture was diluted with a small amount of water and vacuum filtered through celite. The filtrate was concentrated and partitioned with 10 L of ethyl acetate and 8 L of H2O. The aqueous phase was extracted with ethyl acetate (2×2 L). The combined organics were washed with 5 L brine, dried (MgSO4) and vacuum filtered. The solution was concentrated in vacuo to give 2133 g (100% yield) of 5-methoxy-2-(tetrahydro-2H-pyran-2-yl)-3(2H) -pyridazinone as a dark oil which later crystallized to give a tan product suitable for further transformations. The product was purified by recrystallization from ethyl acetate/cyclohexane to give a white solid, mp=76°-78° C. Anal. Calc. for C10H14N2O3 : C,57.13; H,6.71; N,13.32

Workup

  1. filtrationfiltered through celite
  2. concentrationThe filtrate was concentrated
  3. custompartitioned with 10 L of ethyl acetate and 8 L of H2O
  4. extractionThe aqueous phase was extracted with ethyl acetate (2×2 L)
  5. washThe combined organics were washed with 5 L brine
  6. dry with materialdried (MgSO4) and vacuum
  7. filtrationfiltered
  8. concentrationThe solution was concentrated in vacuo

Sources & evidence

ORD record
ord-dd60e0f13ea84b63879f394c72be1ef5
Source dataset
uspto-grants-1997_04
Patent number
US05623072

Reaction notes

Loading…