Triethylamine → tert-Butyl 4-(methoxy(methyl)carbamoyl)piperidine-1-carboxylate

A solution of 1-(1,1-Dimethylethyloxycarbonyl)-4-piperidine carboxylic acid (11.3 g, 49.3 mmol), N,O-dimethylhydroxylamine hydrochloride (5.77 g, 59.1 mmol), 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (11.33 g, 59.1 mmol), 4-dimethylaminopyridine (602 mg, 4.93 mmol) and triethylamine (14.96 g, 148.0 mmol) in dichloromethane (200 mL) was stirred at room temperature for 18 h. The mixture was concentrated to ca. 25 mL, then was poured into 1M hydrochloric acid (75 mL) and extracted with ethyl acetate (3×75 mL). The organic extracts were washed sequentially with 1M hydrochloric acid (50 mL), 10% (w/v) aqueous sodium carbonate (2×50 mL) and brine (50 mL), combined, dried over Na2SO4, filtered and evaporated to afford the title compound as a clear syrup (12.0 g, 44.1 mmol, 89%). 1H NMR CDCL3 : δ4.2 (brm, 2H, eq-H--C(2)), 3.72 (s, 3H, ° CH3), 3.19 (s, 3H, NCH3), 2.8 (brm, 3H, ax-H--C(2), H--C(4)), 1.7 (brm, 4H, H--C(3)), 1.46 (s, 9H, (CH3)3C).

1. concentrationThe mixture was concentrated to ca. 25 mL
2. additionwas poured into 1M hydrochloric acid (75 mL)
3. extractionextracted with ethyl acetate (3×75 mL)
4. washThe organic extracts were washed sequentially with 1M hydrochloric acid (50 mL), 10% (w/v) aqueous sodium carbonate (2×50 mL) and brine (50 mL)
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. customevaporated

ORD record

ord-9c74a344c4ea454a9ce438457076ae2b

Source dataset

uspto-grants-1998_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05719166