Sodium Hydroxide → 1-methyl-5-(3-nitrophenyl)-1H-Tetrazole

Temperatur

0 °C

In a dry flask N-methyl-3-nitro-benzamide (30.0 g, 167 mmol) was dissolved in acetonitrile (835 mL) and sodium azide (10.9 g, 167 mmol) was added and the reaction cooled in an ice bath. Triflic anhydride (29 mL, 172 mmol) was added dropwise to maintain the internal temperature below 3° C. The reaction mixture was stirred for 3.5 hours at 0° C. The reaction mixture was poured into 1N aqueous sodium hydroxide (100 mL). The organic layer was separated dried with sodium sulfate, filtered, and concentrated in vacuo to 50 mL. The solution was diluted with dichloromethane and added water to precipitate a yellow solid (18.46 g, 54%). A second crop of crystals was obtained by concentrated the filtrate in vacuo and adding it to boiling ethyl acetate. Upon cooling to 0° C., 6.07 g (18%) of additional material was isolated upon filtration further purification. 1H NMR (300 MHz, CDCl3), δ: 8.67 (m, 1H), 8.49 (dd, J=8, J′=2, 1H), 8.31 (d, J=8, 1H), 7.94 (dd, J=8, J′=8, 1H), 4.22 (s, 3H).

1. temperaturethe reaction cooled in an ice bath
2. temperatureto maintain the internal temperature below 3° C
3. customThe organic layer was separated
4. dry with materialdried with sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo to 50 mL
7. additionThe solution was diluted with dichloromethane
8. additionadded water
9. customto precipitate a yellow solid (18.46 g, 54%)
10. customA second crop of crystals was obtained
11. concentrationby concentrated the filtrate in vacuo
12. additionadding it
13. temperatureUpon cooling to 0° C.

ORD-Eintrag

ord-19e7a2214c864fb88d43d8adf3b2f663

Quelldatensatz

uspto-grants-2005_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06949546B2