Dibutyltin oxide → HCID 178509305, compound

To a solution of 4-amino-furazan-3-carbonitrile (0.10 g, 0.90 mmol) and trimethylsilyl azide (0.21 g, 1.82 mmol) in toluene (10 mL) was added dibutyl tin oxide (0.227 g, 0.91 mmol) and the mixture was heated for 20 hours at 130° C. until complete consumption of nitrile was observed by LC-MS. The reaction mixture was allowed to cool to ambient temperature and concentrated in vacuo. The residue was dissolved in methanol and partitioned between ethyl acetate and 10% sodium bicarbonate solution and the organic portion was washed with a further portion of 10% sodium bicarbonate solution. The combined aqueous extracts were acidified to pH 2 with 10% HCl solution and re-extracted into ethyl acetate (2×30 mL). The combined organics were dried over MgSO4, filtered and concentrated in vacuo to yield 4-(1H-tetrazol-5-yl)-furazan-3-ylamine as a white solid (0.122 g, 87%).

1. concentrationconcentrated in vacuo
2. dissolutionThe residue was dissolved in methanol
3. custompartitioned between ethyl acetate and 10% sodium bicarbonate solution
4. washthe organic portion was washed with a further portion of 10% sodium bicarbonate solution
5. extractionre-extracted into ethyl acetate (2×30 mL)
6. dry with materialThe combined organics were dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD record

ord-c4b11abf6770440298373bc1b0762931

Source dataset

uspto-grants-2007_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07157476B2