Diisopropylethylamine → HCID 59909827, compound

An ice-cooled solution of (2R)-2-[2-(tert-butoxy)-2-oxoethyl]-5-cyclohexylpentanoic acid (Preparation 168) (6.40 g, 21.45 mmol) in dichloromethane (75 ml) was treated sequentially with 1-hydroxybenzotriazole hydrate (3.19 g, 23.60 mmol), threonine methyl ester hydrochloride (4.00 g, 23.60 mmol), N,N-diisopropylethylamine (7.85 ml, 45.10 mmol) and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (4.52 g, 23.58 mmol) and the mixture was stirred for 17 hours being allowed to warm to room temperature over this time. The solvent was removed under reduced pressure and the residue was dissolved in ethyl acetate then washed sequentially with water, aqueous citric acid solution (10% w/v), a saturated aqueous sodium hydrogen carbonate solution and brine, dried over anhydrous magnesium sulphate, filtered and the solvent removed under reduced pressure. The residue was dissolved in diethyl ether (100 ml) and treated with pentane (150 ml) to produce a white precipitate. This was filtered off and washed with pentane to afford the title compound as a white powder (6.48 g).

1. customThe solvent was removed under reduced pressure
2. dissolutionthe residue was dissolved in ethyl acetate
3. washthen washed sequentially with water, aqueous citric acid solution (10% w/v)
4. dry with materiala saturated aqueous sodium hydrogen carbonate solution and brine, dried over anhydrous magnesium sulphate
5. filtrationfiltered
6. customthe solvent removed under reduced pressure
7. dissolutionThe residue was dissolved in diethyl ether (100 ml)
8. additiontreated with pentane (150 ml)
9. customto produce a white precipitate
10. filtrationThis was filtered off
11. washwashed with pentane

ORD record

ord-32775e3e94244b82aa353b42d777dab1

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06716861B2