C([O-])C.[Na+].[CH3:5][CH2:6][C:7](=[O:13])[CH2:8][C:9](=[O:12])[CH2:10][CH3:11].[I-].[K+].[CH2:16]([N:23]1[C:27]([CH2:28]Cl)=[CH:26][N:25]=[CH:24]1)[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1.Cl.C(N1C(CCl)=CN=C1)C1C=CC=CC=1>C(O)C>[CH2:16]([N:23]1[C:27]([CH2:28][CH:8]([C:7](=[O:13])[CH2:6][CH3:5])[C:9](=[O:12])[CH2:10][CH3:11])=[CH:26][N:25]=[CH:24]1)[C:17]1[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=1
To a solution of 3.75 ml (10 mmol; ˜21% solution in ethanol) sodium ethanolate in 40 ml dry ethanol were added 1.30 mg (10 mmol) 3,5-heptanedione and stirred at 50° C. for 30 min. Then a tip of spatula of potassium iodide was added followed by a solution of 1-benzyl-5-chloromethyl-1H-imidazole (prepared from 2.27 g (9.4 mmol) 1-benzyl-5-chloromethyl-1H-imidazole hydrochloride in 10 ml ethanol and 3.5 ml (9.4 mmol; ˜21% solution in ethanol). The mixture was heated to 50° C. for further 5 min and then immediately cooled to ambient temperature and concentrated under reduced pressure at max. 30° C. Purification by flash-chromatography on silica gel with heptane/ethyl acetate 1:1 as eluent provided 4-(3-benzyl-3H-imidazol-4-ylmethyl)-heptane-3,5-dione as light yellow waxy solid: MS (ISP): 299.2 ((M+H)+.).
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