tert-Butanol → tert-butyl N-(1,3-thiazol-4-yl)carbamate

Thiazole-4-carboxylic acid (6.46 g, 50.0 mmol) was slurried in tert-butyl alcohol (280 mL). Triethylamine (7.68 mL, 55.1 mmol) and diphenylphosphonic azide (11.9 mL, 55.1 mmol) were added and the reaction mixture heated at reflux for 18 hours. The reaction mixture was concentrated in vacuo and the residue dissolved in ethyl acetate. The organics were washed successively with water, 5% aqueous citric acid solution, water, saturated aqueous sodium bicarbonate and brine. The organic phase was dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was purified by silica gel chromatography (ISCO™ column, hexanes to ethyl acetate gradient elution) then triturated with 20% tert-butylmethyl ether in hexanes. The solid was collected by filtration and dried in vacuo to afford the title compound as a white solid (6.48 g).

1. temperaturethe reaction mixture heated
2. temperatureat reflux for 18 hours
3. concentrationThe reaction mixture was concentrated in vacuo
4. dissolutionthe residue dissolved in ethyl acetate
5. washThe organics were washed successively with water, 5% aqueous citric acid solution, water, saturated aqueous sodium bicarbonate and brine
6. dry with materialThe organic phase was dried over anhydrous magnesium sulfate
7. concentrationconcentrated in vacuo
8. customThe residue was purified by silica gel chromatography (ISCO™ column, hexanes to ethyl acetate gradient elution)
9. customthen triturated with 20% tert-butylmethyl ether in hexanes
10. filtrationThe solid was collected by filtration
11. customdried in vacuo

ORD record

ord-e126a7d2fa81432db9efb19842f7a56e

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09145407B2