Oxalyl chloride → HCID 15980920, compound

To a mixture of 4-azidobenzoic acid (200 mg, 1.23 mmol) and oxalyl chloride (5 mL) was added a catalytic quantity of DMF (50 μL). The reaction mixture was stirred for 20 minutes and was concentrated in vacuo. Benzene (20 mL) was added and the mixture was again concentrated in vacuo. The resulting residue was dissolved in DCM (5 mL) and was treated with (5-amino-pyridin-2-yloxy)-acetic acid methyl ester (242 mg, 1.33 mmol) followed by DIPEA (427 μL, 2.46 mmol). The reaction mixture was stirred for 15 h at ambient temperature before being diluted with DCM, washed with water and brine and dried over magnesium sulfate. Filtration and concentration in vacuo gave a residue that was taken up in a small portion of ethyl acetate (5 mL) and was precipitated through the addition of hexanes (50 mL). The solids were collected by vacuum filtration on a fritted glass funnel to afford 164 mg (41%) of (5-(4-azido-benzoylamino)pyridin-2-yloxy)acetic acid methyl ester as a solid: 1H NMR (300 MHz, DMSO-d6) δ 10.25 (bs, 1H), 8.39 (m, 1H), 8.00 (m, 3H), 7.24 (m, 2H), 6.92 (m, 1H), 4.87 (s, 2H), 3.63 (s, 3H); MS (EI) m/z 326.12 (M−H)−.

1. concentrationwas concentrated in vacuo
2. additionBenzene (20 mL) was added
3. concentrationthe mixture was again concentrated in vacuo
4. dissolutionThe resulting residue was dissolved in DCM (5 mL)
5. stirringThe reaction mixture was stirred for 15 h at ambient temperature
6. washwashed with water and brine
7. dry with materialdried over magnesium sulfate
8. filtrationFiltration and concentration in vacuo
9. customgave a residue that
10. customwas precipitated through the addition of hexanes (50 mL)
11. filtrationThe solids were collected by vacuum filtration on a fritted glass funnel

ORD record

ord-b22d72c1fc584095a3204ee0bc8ad297

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07151112B1