Br[C:2]1[N:3]=[N:4][C:5]([CH2:8][CH3:9])=[CH:6][CH:7]=1.[NH:10]1[CH2:20][CH2:19][CH:13]([C:14](OCC)=[O:15])[CH2:12][CH2:11]1.C(N(C(C)C)CC)(C)C.CN1CCCC1>O>[CH2:8]([C:5]1[N:4]=[N:3][C:2]([N:10]2[CH2:20][CH2:19][CH:13]([CH2:14][OH:15])[CH2:12][CH2:11]2)=[CH:7][CH:6]=1)[CH3:9]1.67 g (0.011 mol) of 3-bromo-6-ethylpyridazine was added to 1.5 mL (10 mmol) ethyl isonipecotate and 3.5 mL (20 mmol) diisopropylethylamine and 5 mL N methylpyrrolidine (NMP). This mixture was heated to 140° C. for 4 hours. Upon cooling 100 mL of water was added to the mixture and the contents were extracted with methylene chloride then washed twice with water and once with brine and the solvent evaporated in vacuo. The resulting oil was eluted through a short silica gel plug with 80% ethyl acetate and 20% hexanes and dried in vacuo. This intermediate was taken up in 25 mL THF and was exposed to 3-fold excess lithium aluminum hydride with stirring under nitrogen for 1 hour. The reaction was chilled on ice and quenched by dropwise addition of water. The slurry was dried, treated with charcoal and filtered yielding 6-ethyl-3-(4-hydroxymethyl-1-piperidinyl)pyridazine (Formula IV: R1 =C2H5 ; Y=CH2 ).
Wird geladen…
