Carbamic acid, 1H-1,2,4-triazol-3-yl-, 1,1-dimethylethyl ester (9CI) synthesis

Yield:160416-01-3 61%

Reaction Conditions:

with N,N,N,N,-tetramethylethylenediamine in hexane at 20; for 24 h;

Steps:

31.A

To a RT slurry of 3-amino-1,2,4-triazole (1.0 g, 11.9 mmol)in hexanes (20 mL) was added TMEDA (0.07 g, 0.6 mmol) and di-tert-butyl dicarbonate (3.89 g, 17.8 mmol). The reaction mixture was stirred at RT for 24 h, poured into sat. aqueous NaHCO₃ (150 mL) and the product was extracted with EtOAc (2×25 mL). The organic extracts were combined, dried (MgSO₄) and concentrated in vacuo. The residue was chromatographed (SiO₂: continuous gradient from 0% EtOAc/Hexane to 100% EtOAc/Hex) to give the desired Part A compound (1.33 g, 61% yield) as a white solid. [M+H]⁺=185.0; ¹H NMR (400 MHz, CDCl₃): δ 7.48 (s, 1H), 1.66 (s, 9H)

References:

US2008/9465,2008,A1 Location in patent:Page/Page column 54-55