[C:1]([CH2:3][CH2:4][CH2:5][CH2:6][C:7]1[N:12]2[CH:13]=[N:14][CH:15]=[C:11]2[CH:10]=[CH:9][CH:8]=1)#[N:2].[N-:16]=[N+:17]=[N-:18].[Na+].[Cl-:20].[NH4+].[Cl-].[Li+]>CN(C)C=O>[ClH:20].[NH:16]1[C:1]([CH2:3][CH2:4][CH2:5][CH2:6][C:7]2[N:12]3[CH:13]=[N:14][CH:15]=[C:11]3[CH:10]=[CH:9][CH:8]=2)=[N:2][N:18]=[N:17]1A mixture of 5-(4-cyanobutyl)-imidazo[1,5-a]pyridine (4.0 g), sodium azide (1.88 g), ammonium chloride (1.57 g) and lithium chloride (10 mole %) in 14 ml of dry dimethylformamide is heated at 125° for 17 hours. The reaction mixture is cooled, filtered and evaporated to a residual oil which is redissolved in 50 ml of water and extracted with ethyl acetate (50 ml). The aqueous phase is adjusted to pH=2 and extracted with ethyl acetate and then adjusted to pH=5. The resulting solid is collected by filtration and converted to its hydrochloride salt which is recrystallized from acetone/methanol to yield 5-[4-(5-tetrazolyl)butyl]-imidazo[1,5-a]pyridine monohydrochloride, m.p. 159°-161°.
Loading…
