Methyl chloroformate → Carbamic acid, N-(1,1-dimethylethyl)-N-(3-methyl-2-pyridinyl)-, methyl ester

To N-(tert-butyl)-3-methylpyridin-2-amine (67) (16.78 g, 92% wt, 102 mmol) in THF (100 ml) was addition MeMgCl (44.3 mL, 3M, 133 mmol) in THF under −10° C. over 5 min. The reaction mixture was warmed up to room temperature and aged for 80 min, then cooled to −20 to −15° C. and methyl chloroformate (8.7 ml, 112 mol) was added over 10 min under −8° C. The reaction mixture was gradually warmed up and aged overnight at room temperature. The reaction mixture was quenched by addition of 15% aqueous citric acid (13 mL), water (40 mL) and MTBE (33 mL) at 0° C. The organic layer was separated and washed with water (50 mL), saturated NaHCO3/water (1:3, 50 ml), brine (50 mL) and water (50 mL), in turns. The organic layer was concentrated and flushed with THF to give 68 (19.3 g, 92%).

1. temperaturecooled to −20 to −15° C.
2. temperatureThe reaction mixture was gradually warmed up
3. customThe reaction mixture was quenched by addition of 15% aqueous citric acid (13 mL), water (40 mL) and MTBE (33 mL) at 0° C
4. customThe organic layer was separated
5. washwashed with water (50 mL), saturated NaHCO3/water (1:3, 50 ml), brine (50 mL) and water (50 mL), in turns
6. concentrationThe organic layer was concentrated
7. customflushed with THF

ORD record

ord-d6541613b6784ed4a9d37943f8ff707a

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09174989B2