Water → HCID 19107658, compound

Powdered sodium azide (19.5 g, 0.3 mol) was added in portions, over 5 minutes, to a stirred solution of ethyl 2-bromo-2,2-difluoroacetate (50.74 g, 0.25 mol) in dry dimethyl sulfoxide (250 mL). After stirring at room temperature for 18 hours, the mixture was poured into water (750 mL) and extracted with methylene chloride (4×100 mL). The combined extracts were washed with water (4×100 mL), dried over anhydrous magnesium sulfate, then filtered, and the filtrate was distilled at atmospheric pressure through an indented (10 cm.) distillation column, at a bath temperature of 77° C., until no more methylene chloride distilled. 1H NMR spectroscopy (CDCl3 ; (CH3)4Si internal standard) of the colorless residue showed a mixture of methylene chloride (31 mol %) and the azido ester (69 mol%); 4.53 (q, 2H, CH2), 1.44 (t, 3H, CH3). This corresponds to a yield of 34.44 g (83.4%) of the azido ester. The pure product was obtained as a colorless liquid by distillation under vacuum; bp 68° C./100 mm. 19F NMR (CDCl3, CFCl3 internal standard) φ 84.8 (s). Anal. Calcd. for C4H5F2N3O2 : C, 29.10; H, 3.05; N, 25.45; F, 23.02. Found: C, 28.80; H, 3.15; N, 25.36; F, 23.15.

1. extractionextracted with methylene chloride (4×100 mL)
2. washThe combined extracts were washed with water (4×100 mL)
3. dry with materialdried over anhydrous magnesium sulfate
4. filtrationfiltered
5. distillationthe filtrate was distilled at atmospheric pressure through an indented (10 cm.) distillation column, at a bath temperature of 77° C.
6. distillationuntil no more methylene chloride distilled
7. additiona mixture of methylene chloride (31 mol %)
8. customThe pure product was obtained as a colorless liquid by distillation under vacuum

ORD record

ord-9f2b80946da44e98882566382e8a991d

Source dataset

uspto-grants-1994_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05276171