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ChemicalBook CAS DataBase List Carbamic acid, (5-methyl-3-pyridinyl)-, 1,1-dimethylethyl ester (9CI)
631910-23-1

Carbamic acid, (5-methyl-3-pyridinyl)-, 1,1-dimethylethyl ester (9CI) synthesis

4synthesis methods
-

Yield:631910-23-1 88%

Reaction Conditions:

Stage #1: 5-methylpyridin-3-aminewith sodium hexamethyldisilazane in tetrahydrofuran at 20; for 0.25 h;
Stage #2: di-tert-butyl dicarbonate in tetrahydrofuran at 20;

Steps:



To a solution of 5-methylpyridin-3-amine (5 g, 46 mmol) in THF (80 mL) at r.t. was added 1M sodium bis(trimethylsilylamide) in THF (101 mL, 101 mmol), stirred for 15 min, followed by di-tert-butyldicarbonate (11 g, 49 mmol) in THF (20 mL). The reaction was stirred at r.t overnight and concentrated. The concentrate was treated with 0.2M HCl (60 mL) and EtOAc, and the organic layer was extracted, washed with NaHCO3(sat.) and brine, dried over Na2SO4, filtered and concentrated. The concentrate was purified using flash chromatography on silica gel (40% EtOAc:Hexane) to give a yellow solid as product tert-butyl 5-methylpyridin-3-ylcarbamate (8.5 g, 88% yield). LCMS (m/z): 209.1 (MH+); LC Rt=1.94 min. 1H NMR(CDCl3) δ 8.20(d, 1H), 8.12(s, 1H), 7.86(s, 1H), 6.53(s, 1H), 2.33(s, 3H), 1.53(s, 9H).

References:

US2010/216839,2010,A1 Location in patent:Page/Page column 24