Ethyl diazoacetate → HCID 10707551, compound

Temperature

80 °C

To a solution of (1-(hydroxymethyl)propyl)carbamic acid tert-butylester (7.2 g, 39 mmol) in 1,2-dichloroethane (500 ml) rhodium(II)acetate (180 mg) was added and the mixture was heated to 80° C. Ethyldiazoacetate (6.0 ml, 57 mmol) in 1,2-dichloroethane (180 ml) was added over a period of 60 min and the mixture was heated at 80° C. for 6 hours. Then another portion of ethyldiazoacetate (2.0 ml, 19 mmol) in 1,2-dichloroethane (40 ml) was added and the mixture was refluxed for 7 hours. The mixture was cooled to room temperature and washed with sodium bicarbonate (2×100 ml) and brine (100 ml), dried over magnesium sulfate and concentrated in vacuo. The crude product was chromatographed on silica (300 g) is with pentane/ethyl acetate 7:3 as eluent to give 4.3 g of (2-(tert-butoxycarbonylamino)butoxy)acetic acid ethylester. The product was dissolved in of 1 M lithium hydroxide in water/methanol 1:3 (40 ml) and stirred at room temperature for 4 hours. The mixture was concentrated in vacuo and water (100 mL) was added and the solution was washed with ether (20 mL). The aqueous phase was acidified to pH 4 with 1 M aqueous hydrogen chloride and extracted with ethyl acetate (200 ml), dried over magnesium sulfate and concentrated in vacuo to give 2.46 g of (2-(tert butoxycarbonylamino)butoxy)acetic acid.

1. temperaturethe mixture was heated at 80° C. for 6 hours
2. temperaturethe mixture was refluxed for 7 hours
3. temperatureThe mixture was cooled to room temperature
4. washwashed with sodium bicarbonate (2×100 ml) and brine (100 ml)
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated in vacuo
7. customThe crude product was chromatographed on silica (300 g)

ORD record

ord-6cbdc22491b64dcba995903cfe864a47

Source dataset

uspto-grants-2000_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06127391