3-(4-Pyridinyl)-2-cyclohexen-1-one oxime → 1-(4-Pyridinyl)-hexan-1,5-dione
Reaktionsgleichung
N1C=CC(C2CCCC(=NO)C=2)=CC=1.[O:15]=[C:16]([CH3:33])[CH2:17][CH2:18][CH:19]([C:25]([C:27]1[CH:32]=[CH:31][N:30]=[CH:29][CH:28]=1)=[O:26])C(OCC)=O>>[N:30]1[CH:31]=[CH:32][C:27]([C:25](=[O:26])[CH2:19][CH2:18][CH2:17][C:16](=[O:15])[CH3:33])=[CH:28][CH:29]=1Komponenten
3
Versuchsvorschrift
An improvement in the process for preparing 3-(4-pyridinyl)-2-cyclohexen-1-one oxime by heating ethyl 5-oxo-2-[(4-pyridinyl)carbonyl]hexanoate under aqueous acidic conditions to produce 1-(4-pyridinyl)-hexan-1,5-dione, heating said hexan-1,5-dione with a basic condensing agent to produce 3-(4-pyridinyl)-2-cyclohexen-1-one, and converting said cyclohexen-1-one to its oxime, said improvement being a one pot sequence consisting of first heating ethyl 5-oxo-2-[(4-pyridinyl)carbonyl]hexanoate with excess aqueous sulfuric acid, neutralizing the excess acid, shaking the resulting warm mixture well with isopropyl alcohol to extract the 3-(4-pyridinyl)-2-cyclohexen-1-one, draining off the heavier warm aqueous layer, adding hydroxylamine hydrochloride to the isopropyl alcohol solution of 3-(4-pyridinyl)-2-cyclohexen-1-one, stirring the mixture at reflux, basifying the mixture and evaporating the reaction mixture to dryness, and isolating the 3-(4-pyridinyl)-2-cyclohexen-1-one oxime from the residue.