N-(tert-butoxycarbonyl)glycine → HCID 76698467, compound

HATU (46.9 g, 123.30 mmol) was added to a stirred solution of 2-(tert-butoxycarbonylamino)acetic acid (18 g, 102.75 mmol) DMA (230 mL) at ambient temperature. After 5 minutes a solution of (2S,3R)-methyl 2-amino-3-hydroxybutanoate hydrochloride (17.43 g, 102.75 mmol) and DIPEA (71.8 mL, 411.00 mmol) in DMA (230 mL) was added and the resulting solution was stirred at ambient temperature for 20 hours, The reaction mixture was diluted with EtOAc (300 mL), and washed with 1N citric acid (300 mL), salt was added to the aqueous layer which was re extracted with EtOAc (4×400 mL). The organic extracts were combined, washed with saturated NaHCO3 (200 mL), dried over MgSO4, filtered and evaporated to afford crude product. The crude product was purified by flash silica chromatography, elution gradient 50 to 100% EtOAc in isohexane. Pure fractions were evaporated to dryness to afford the title compound (12.97 g, 43.5%) as a yellow glass which formed a solid on standing.

1. washwashed with 1N citric acid (300 mL), salt
2. additionwas added to the aqueous layer which
3. extractionwas re extracted with EtOAc (4×400 mL)
4. washwashed with saturated NaHCO3 (200 mL)
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. customevaporated
8. customto afford crude product
9. customThe crude product was purified by flash silica chromatography, elution gradient 50 to 100% EtOAc in isohexane
10. customPure fractions were evaporated to dryness

ORD record

ord-03f5f5cec1204091a8ce7a7c8f6cde7c

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07994179B2